AMERICAN CENTURY MUTUAL FUNDS INC
N-30D, 1997-06-27
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                                SEMIANNUAL REPORT


                            [american century logo]


                                 APRIL 30, 1997



                                    TWENTIETH
                                     CENTURY
                                      GROUP


                                      Ultra
                                      Vista



[front cover]



                                TABLE OF CONTENTS


Report Highlights.............................................................1
Our Message to You............................................................2
Period Overview...............................................................3
Ultra
     Performance & Portfolio Information......................................4
     Management Q & A.........................................................5
     Schedule of Investments..................................................8
Financial Highlights.........................................................26
Vista
     Performance & Portfolio Information.....................................11
     Management Q & A........................................................12
     Schedule of Investments.................................................16
Financial Highlights.........................................................29
Statements of Assets and Liabilities.........................................18
Statements of Operations.....................................................19
Statements of Changes in Net Assets..........................................20
Notes to Financial Statements................................................21
Share Class and Retirement
   Account Information.......................................................32
Background Information
     Investment Philosophy and Policies......................................36
     Comparative Indices.....................................................36
     Fund Management Team Leaders............................................36
Glossary.....................................................................37


American Century  Investments offers you nearly 70 fund choices covering stocks,
bonds, money markets,  specialty investments and blended portfolios. To help you
find the funds that may meet your needs, we have divided  American Century funds
into three groups based on investment style and objectives.  These groups, which
appear below, are designed to help simplify your fund decisions.


                  AMERICAN CENTURY INVESTMENTS--FAMILY OF FUNDS


     Benham Group(R)         American Century Group   Twentieth Century(R) Group

  MONEY MARKET FUNDS         ASSET ALLOCATION &
 GOVERNMENT BOND FUNDS         BALANCED FUNDS               GROWTH FUNDS
DIVERSIFIED BOND FUNDS    CONSERVATIVE EQUITY FUNDS      INTERNATIONAL FUNDS
 MUNICIPAL BOND FUNDS          SPECIALTY FUNDS

                                                               Ultra
                                                               Vista



We welcome your comments or questions about this report.  
See the back cover for ways to contact us by mail, phone or e-mail.

Twentieth  Century and the Benham Group are registered marks of American Century
Services Corporation and Benham Management Corporation,  respectively.  American
Century is a service mark of American Century Services Corporation.


                                                    American Century Investments


                                REPORT HIGHLIGHTS


PERIOD OVERVIEW

o    The U.S. stock market  produced widely  divergent  returns over the period.
     The S&P 500's 14.74% six-month total return continued a three-year trend of
     unusually  strong  performance by large-cap  stocks.  By contrast,  the S&P
     MidCap 400 posted a 6.88% return,  and the small-cap  Russell 2000 returned
     just 1.61%.

o    Factors that were in the S&P 500's favor included: equity investors seeking
     stability and liquidity; strong economic growth with low inflation; and the
     success of index funds.

o    The fast-growing  companies targeted by Ultra and Vista didn't benefit from
     the  factors  that drove  investors  to the S&P 500.  They  lagged  despite
     reporting strong earnings growth in most cases.

ULTRA

o    Ultra  posted a modest 4.35% total return in a period that didn't favor its
     investment  approach.  Ultra's  returns  for the  five-year,  ten-year  and
     life-of-fund periods ended April 30 remained higher than the S&P 500's.

o    We've remained  focused on long-term  results,  concentrating on businesses
     with the strongest fundamental outlooks we can find.

o    We increased  positions  in consumer  product  companies  such as Procter &
     Gamble, pharmaceutical producers such as Warner-Lambert,  and semiconductor
     manufacturers such as Intel. All displayed strong growth prospects.

o    We reduced positions in computer  software,  networking and  communications
     companies where increased competition has led to lower profit margins.

VISTA

o    Vista  suffered  one of the  steepest  short-term  declines  in its 13-year
     history.  The drop resulted  from the decline in mid- and small-cap  growth
     stocks,  compounded  by our  focus on the most  rapidly  growing  companies
     within that group. The Russell 2500 Growth Index,  which represents a blend
     of small- and mid-cap stocks, posted a -3.73% total return.

o    The  technology  sell-off  allowed us to build  positions in more seasoned,
     high quality names.  These are the stocks we believe will rebound  strongly
     when the market again favors fast-growing companies.

o    We  increased   holdings  in   semiconductor   companies,   circuit   board
     manufacturers and energy services  companies.  We reduced computer software
     and business  services  holdings because of increasing  competition and low
     barriers to entry in those industries.


     ULTRA
     -----------------------------------------
     INVESTOR CLASS(1)
     -----------------------------------------
     Total Returns:        AS OF 4/30/97

         6 Months          4.35%(2)
         1 Year            10.69%
     -----------------------------------------
     Net Assets:           $18.9 billion
         (AS of 4/30/97)
     -----------------------------------------
     Inception Date:       11/2/81
     -----------------------------------------
     Ticker Symbol:        TWCUX
     -----------------------------------------


     VISTA
     -----------------------------------------
     INVESTOR CLASS(1)
     -----------------------------------------
     Total Returns:        AS OF 4/30/97
         6 Months          -20.79%(2)
         1 Year            -23.56%
     -----------------------------------------
     Net Assets:           $1.6 billion
         (AS of 4/30/97)
     -----------------------------------------
     Inception Date:       11/25/83
     -----------------------------------------
     Ticker Symbol:        TWCVX
     -----------------------------------------


     (1) See Share Classes, page 32.
     (2) Not annualized.


- --------------------------------------------------------------------------------
             Many of the investment terms in this report are defined
                          in the Glossary on page 37.
- --------------------------------------------------------------------------------



Semiannual Report                                          Report Highlights   1


                               OUR MESSAGE TO YOU


           [Photo of James E. Stowers, Jr. and James E. Stowers III]

April 30,  1997,  marked the end of an  eventful  period for the company and the
Twentieth Century aggressive growth funds. We entered 1997 with a new identity--
American Century  Investments.  American Century encompasses the skills,  talent
and resources  brought  together  when  Twentieth  Century  Mutual Funds and The
Benham Group merged during 1995 and 1996.

Changing the company's name after being known as Twentieth  Century Mutual Funds
for  almost  40 years  was a  significant  step.  Although  our core  investment
disciplines  remain  unchanged,  the combination of Twentieth Century and Benham
allows us to bring you a full menu of nearly 70 funds.  Our offerings range from
conservative  money  market  funds  carrying  the Benham name to the nine growth
funds that  still  carry the  Twentieth  Century  name and  employ our  hallmark
growth-oriented investment approach.

The six-month period ended April 30, 1997, was a challenge for aggressive growth
funds  such as  Ultra  and  Vista.  As  investors  sought  size,  stability  and
familiarity,  the S&P 500 and funds that  mirror the index  outperformed  growth
funds investing in smaller companies and emerging industries.  These factors had
an especially large impact on the short-term performance of Vista.

Given this environment, it is important to remember that investing in aggressive
growth  funds  involves  significant  short-term  volatility.  This  is  why  we
encourage  investors  to hold them for  periods of five years or more.  Over the
long term, an  aggressive  growth  strategy can provide the kind of  significant
capital growth that builds wealth.  However,  investors need patience to weather
the market's cycles and realize the strategy's potential benefits.

We have steadily refined the growth  discipline  pioneered at Twentieth  Century
over the past 25 years,  enabling our teams to identify and invest in businesses
that are among the  fastest-growing  in the  world.  We are  confident  that our
approach will continue to reward patient investors who stay the course.

A large part of helping investors remain patient and confident in their funds is
providing the best possible information  regularly in a helpful format. Based on
investors'  feedback,  we have redesigned our shareholder reports to include new
features such as a one-page report summary, a glossary,  more charts and graphs,
and expanded  Management Q&A and background  information  sections.  This report
displays the new format.

We appreciate your confidence in American Century and look forward to continuing
to serve you.


Sincerely,


/s/James E. Stowers, Jr.                   /s/James E. Stowers III
James E. Stowers, Jr.                      James E. Stowers III
Chairman of the Board and Founder          President and Chief Executive Officer



2    Our Message to You                             American Century Investments



                                 PERIOD OVERVIEW

[line graph - data below]

            U.S. STOCK MARKET PERFORMANCE (Growth of $1.00)
            For the six monthes ended April 30, 1997
            ------------------------------------------------------------
            DATE             S&P 500           S&P 400      RUSSELL 2000

            10/31/96         $1.00             $1.00            $1.00
            11/30/96         $1.07             $1.06            $1.04
            12/31/96         $1.06             $1.06            $1.07
            1/31/97          $1.12             $1.10            $1.09
            2/28/97          $1.13             $1.09            $1.06
            3/31/97          $1.08             $1.04            $1.01
            4/30/97          $1.15             $1.07            $1.02


WIDELY DIVERGENT RETURNS

The six-month period ended April 30, 1997, produced widely divergent returns for
U.S.  stock  investors.  In general,  the shares of large  companies  (large-cap
stocks), particularly relatively stable,  industry-leading firms in the S&P 500,
significantly outperformed the shares of faster-growing, smaller companies (mid-
and small-cap stocks).  Value stocks (shares of companies that are lower priced)
generally   outperformed   growth  stocks  (those  of  companies   demonstrating
above-average  earnings growth) as investors placed a higher premium on earnings
stability than on earnings growth.

STRONG RETURNS FOR THE S&P 500

The S&P 500 typically  represents the large-cap sector of the U.S. stock market.
Many investors also use the index as a proxy for the U.S. market as a whole. The
sustained  advance  of the S&P 500 was  one of the key  success  stories  of the
period. The index posted a 14.74% total return during the six months, continuing
a three-year trend of unusually  strong results.  Factors that supported the S&P
500's performance included:

o Investors  seeking  predictable  earnings  and  liquidity  because they feared
rising interest rates and an economic slowdown. The shares of large,  well-known
firms such as Johnson & Johnson and Microsoft rallied appreciably.

o  Favorable   economic   conditions  (robust  growth  and  low  inflation)  and
particularly strong earnings growth for large-cap companies.

o The popularity and success of S&P 500 index funds.  With more investor dollars
chasing  stocks in the S&P 500, the prices of those shares rose much faster than
the prices of mid- and small-cap stocks.

LOWER RETURNS FOR SMALLER-CAP STOCKS

Many  analysts  use the S&P 400  MidCap  Index  and the  Russell  2000  Index to
represent mid- and small-cap stocks, respectively.  As shown in the accompanying
graph, the S&P 500 significantly outperformed the smaller-cap indices.

While the S&P 500 and its component  companies were considered a relatively safe
haven  during the  period,  many  investors  viewed  mid- and  small-cap  growth
companies as too volatile and unpredictable. As a result, the market priced mid-
and small-cap growth stocks more conservatively, weighting current earnings more
heavily than projected  future  earnings.  Investors also became less willing to
pay a premium for fast-growing technology and healthcare shares.

The resulting price declines were generally based more on market perception than
on actual  fundamental  indicators such as earnings and revenue.  Many companies
experienced  lower share  prices  despite  continuing  to show strong  operating
results.  Defensive-minded  analysts questioned whether the earnings and revenue
projections  of mid- and small-cap  companies  would be realized,  and investors
refused to pay the higher prices these shares have been awarded in the past.


Semiannual Report                                            Period Overview   3


<TABLE>
<CAPTION>
                                      ULTRA

TOTAL RETURNS AS OF APRIL 30, 1997
- ----------------------------------------------------------------------------------------------------------------------------------
                                                                             AVERAGE ANNUAL RETURNS
<S>                               <C>             <C>               <C>              <C>               <C>              <C>   
                           -------------------------------------------------------------------------------------------------------
                                6 MONTHS          1 YEAR            3 YEARS          5 YEARS          10 YEARS       LIFE OF FUND
- ----------------------------------------------------------------------------------------------------------------------------------
INVESTOR CLASS (inception 11/2/81)
- ----------------------------------------------------------------------------------------------------------------------------------
     Ultra.....................   4.35%           10.69%            17.04%           17.50%            16.37%           17.41%
     S&P 500...................  14.74%           25.10%            24.08%           17.07%            14.10%           16.79%

- ----------------------------------------------------------------------------------------------------------------------------------
ADVISOR CLASS (inception 10/2/96)
- ----------------------------------------------------------------------------------------------------------------------------------
     Ultra.....................   4.21%................................................................................  4.11%
     S&P 500...................  14.74%................................................................................ 16.60%

- ----------------------------------------------------------------------------------------------------------------------------------
INSTITUTIONAL CLASS (inception 11/14/96)
- ----------------------------------------------------------------------------------------------------------------------------------
     Ultra.............................................................................................................  0.18%
     S&P 500...........................................................................................................  9.97%


See pages 32, 36 and 37 for more  information  about share classes,  the S&P 500
and returns.
</TABLE>


[line graph - data below]

GROWTH OF $10,000 OVER 10 YEARS (Investor Class)
- --------------------------------------------------------------

                         ULTRA                     S & P
                    ---------------           ---------------
DATE                  ACCT VALUE                ACCT VALUE
- --------------------------------------------------------------
4/30/87                 $10,000                   $10,000
4/30/88                  $8,529                    $9,356
4/30/89                 $10,730                   $11,487
4/30/90                 $10,792                   $12,687
4/30/91                 $16,889                   $14,914
4/30/92                 $20,330                   $17,010
4/30/93                 $23,430                   $18,578
4/30/94                 $28,394                   $19,568
4/30/95                 $30,157                   $22,976
4/30/96                 $41,141                   $29,899
4/30/97                 $45,539                   $37,404



Past  performance  does not  guarantee  future  results.  Investment  return and
principal  value will fluctuate,  and redemption  value may be more or less than
original  cost.  Data quoted is for Investor Class only;  performance  for other
classes will vary due to differences  in fee  structures  (see the Total Returns
table above).

The line representing  Ultra's total return includes operating expenses (such as
transaction  costs and  management  fees) that reduce  returns,  while the total
return line of the S&P 500 does not.



PORTFOLIO AT A GLANCE
- ------------------------------------------------------------------------
                                            4/30/97           10/31/96
Number of Companies                           122               109
Median Price/Earnings Ratio                  24.0              26.8
Portfolio Turnover                           51%(1)            87%(2)
Expense Ratio (for Investor Class)          1.00%(3)          1.00%


(1) Six months ended 4/30/97.

(2) Year ended 10/31/96.

(3) Annualized.




4    Ultra                                          American Century Investments



                                      ULTRA


MANAGEMENT Q & A

An interview with Jim Stowers III and Bruce Wimberly,  portfolio managers on the
Ultra management team.

HOW DID THE FUND PERFORM?

Ultra posted a modest return in a period that primarily rewarded the S&P 500 and
its largest  companies (see the Period Overview on page 3). Ultra's total return
for the six months ended April 30, 1997,  was 4.35%,  compared to 14.74% for the
S&P 500.  The  companies  Ultra  owned  were  growing  faster  than  many of the
companies that powered the S&P 500's ascent,  but investors  placed a premium on
consistency rather than growth.

Unlike  an index  fund,  Ultra  makes no  attempt  to match any  benchmark  over
short-term  periods.  We include the S&P 500 in our  discussions  primarily  for
long-term performance comparisons and because the index is viewed so widely as a
proxy  for the  entire  U.S.  stock  market.  Although  the  S&P 500 has  posted
exceptional  returns over the last three years,  Ultra's  average annual returns
for long-term  periods (the five-year,  ten-year and life-of-fund  periods ended
April 30) remained  higher than the index's (see the  performance  chart on page
4). In pursuing  our growth  investing  discipline,  we continue to believe that
stock  prices  follow  earnings  over the long  run and  that the  markets  will
eventually reward companies that demonstrate accelerating earnings and revenues.

WHAT CHANGES DID YOU MAKE TO THE FUND'S PORTFOLIO DURING THE PERIOD? WHY?

When the stock market  declined in March,  we took  advantage  of falling  share
prices to start  adding  consumer  nondurable  companies  such as  Gillette  and
Procter & Gamble.  We think  these  large-cap  firms offer the  opportunity  for
strong,  sustainable growth, even in the event of an economic downturn, and they
further  diversify  the  fund's  portfolio  by  increasing  its  exposure  to  a
previously underweighted


[bar graph - data below]

ULTRA'S ONE-YEAR RETURNS OVER 10 YEARS(1) (Periods ended April 30)
- --------------------------------------------------------------------------

                         ULTRA                     S & P
                    ---------------           ---------------
DATE                    RETURN                    RETURN
- --------------------------------------------------------------------------
4/30/88                 -14.71%                   -6.44%
4/30/89                 25.81%                    22.78%
4/30/90                  0.58%                    10.44%
4/30/91                 56.51%                    17.56%
4/30/92                 20.37%                    14.05%
4/30/93                 15.25%                     9.22%
4/30/94                 21.18%                     5.33%
4/30/95                  6.21%                    17.42%
4/30/96                 36.42%                    30.13%
4/30/97                 10.69%                    25.10%



This chart  illustrates  the fund's  returns over the past 10 years and compares
them  with the S&P  500's  returns.  Ultra's  total  returns  include  operating
expenses,  while the S&P 500's returns do not. See page 36 for a description  of
the S&P 500. Past performance is no guarantee of future results.

(1) Investor Class.

Semiannual Report                                                     Ultra    5



                                      ULTRA


sector. Gillette and Procter & Gamble are dominant companies in their respective
industries.

We also increased Ultra's holdings in pharmaceutical companies to take advantage
of  a  strong  new  product  cycle.   Large-scale  investment  in  research  and
development by drug companies is starting to result in many new products  coming
to the market. These new drugs,  combined with the favorable  demographic trends
of the aging U.S.  population,  give us confidence  that many  companies in this
industry will see share price appreciation.

One of the drug companies we owned was  Warner-Lambert,  which earned regulatory
approval for two new drugs that combat  problems  associated  with  diabetes and
high cholesterol. The profit margins for these new products are much higher than
those  of the  over-the-counter  health  and  beauty  aids  that  were  once the
company's mainstay.  We think Warner-Lambert will be able to sustain its current
high earnings growth rate, thanks to its new products.

WHAT CHANGES DID YOU MAKE TO THE FUND'S  TECHNOLOGY  HOLDINGS DURING THE PERIOD?
WHY?

The fund's overall weighting in technology stayed about the same,  approximately
35%, but we made numerous changes within the sector.  We added to our electrical
and electronic components position, especially semiconductor companies, where we
believe there are ample growth opportunities. We increased our existing holdings
in Intel, and we added Altera Corp. and LSI Logic to the portfolio.  We continue
to focus on companies  that  demonstrate  market  dominance,  pricing  power and
efficient cost control.

We reduced our  positions in computer  software  and  services,  networking  and
communications  companies.  Rapid growth in these industries in recent years has
caused increased competition, leading to weaker product pricing and lower profit
margins.

WHAT WERE SOME OF THE FUND'S BEST-PERFORMING HOLDINGS DURING THE PERIOD?

Dell Computer  Corp.,  a computer  manufacturer,  was the fund's  top-performing
stock.  Dell's  successful  business  strategy and operations have enabled it to
increase  its  share of the  personal  computer  market.  The  company  recently
announced plans to enter the workstation market. Dell is an excellent example of
the kind of company we look for -- one with accelerating  growth of earnings and
revenues,  a dominant  position in its industry,  increasing  market  share,  an
effective management team, healthy profit margins and strong cash flow.

Another strong contributor to the fund's return was Telecomunicacoes Brasileiras
S.A. (Telebras). Telebras, the Brazilian equivalent of AT&T, has benefited from



TOP TEN HOLDINGS                         % of fund investments
- --------------------------------------------------------------------
                                         As of             As of
                                         4/30/97          10/31/96
Merck & Co., Inc.                         3.9%              3.6%
Intel Corp.                               3.1%              1.9%
Johnson & Johnson                         3.1%              2.6%
Pfizer, Inc.                              3.0%              2.7%
Citicorp                                  2.9%              3.2%
Chase Manhattan Corp.                     2.9%              2.9%
General Electric Co.                      2.8%              1.7%
Dell Computer Corp.                       2.4%              0.6%
Sun Microsystems, Inc.                    2.2%              4.5%
Telecomunicacoes Brasileiras
   S.A. ADR                               2.1%              1.5%




TOP FIVE INDUSTRIES                         % of fund investments
- --------------------------------------------------------------------
                                         As of             As of
                                         4/30/97          10/31/96
Pharmaceuticals                           16.9%             11.3%
Electrical & Electronic Components        11.6%              2.5%
Banking                                   11.1%              8.7%
Computer Systems                           7.1%              6.4%
Computer Software & Services               5.3%             11.5%





6    Ultra                                          American Century Investments



                                      ULTRA


rate restructuring and moves toward privatization. Telebras was the fund's tenth
largest holding as of April 30. 

Eight of the ten top-performing stocks in Ultra ranked in the top 15% of the S&P
500 in terms of market  capitalization.  These eight firms were:  Intel,  Merck,
Johnson & Johnson, Microsoft, Citicorp, Pfizer, BankAmerica and Warner-Lambert.

WHAT WERE SOME OF THE STOCKS THAT REDUCED THE FUND'S RETURNS?

Concerns  about  slowing  computer  sales  caused  three of the  fund's  top ten
holdings  at  the   beginning  of  the  period  --  Sun   Microsystems,   Ascend
Commu-nications  and Cascade  Communications -- to post some of the lowest stock
price  returns  in  the  portfolio  for  the  six  months.  Computer  networking
companies,  including  3Com  Corporation  and  Fore  Systems,  were  also hit by
concerns  about  slower  sales  as large  companies  postponed  purchases  while
evaluating new technology.

WHAT'S YOUR OUTLOOK FOR THE FUND?

Markets are  cyclical.  We've seen  similar  periods in the past when our growth
style and the  stocks we target  were out of  favor,  and large  company  stocks
perceived as relatively safe outperformed the market.  This happens from time to
time, but we don't think it can go on forever. We believe growth will eventually
become  attractive again and the market should reward our style.  Unfortunately,
there is no telling precisely when this might happen or to what degree. We avoid
trying to time the  market  (and we  discourage  fund  investors  from doing so)
because market trends can reverse abruptly and without warning.

Instead,  we continue to manage Ultra in the same manner as we have in the past.
We've  stuck to our basic  investment  disciplines.  We've  remained  focused on
long-term  results,  concentrating  on  keeping  the fund well  positioned  with
investments in good, growing businesses with the strongest  fundamental outlooks
we can find. We expect the  fast-growing  stocks owned in Ultra will  eventually
reward investors for their patience.



Semiannual Report                                                     Ultra    7



                             SCHEDULE OF INVESTMENTS
                                      ULTRA


APRIL 30, 1997 (UNAUDITED)
Shares                          ($ in Thousands)                           Value
- --------------------------------------------------------------------------------
- --------------------------------------------------------------------------------
COMMON STOCKS
- --------------------------------------------------------------------------------
AEROSPACE & DEFENSE -- 2.4%
      1,550,000   AlliedSignal Inc.                                 $    111,988
      1,050,000   Boeing Co.                                             103,556
      2,000,000   British Aerospace PLC ORD                               42,636
      2,500,000   United Technologies Corp.                              189,063
                                                                    ------------
                                                                         447,243
                                                                    ------------

AIRLINES -- 0.2%
        450,000   AMR Corp.(1)                                            41,906
                                                                    ------------

BANKING -- 11.1%
      2,000,000   Bank of Boston Corp.(1)                                145,500
      2,850,000   Bank of New York Co., Inc. (The)                       112,575
      2,800,000   BankAmerica Corp.                                      327,250
      5,900,000   Chase Manhattan Corp.                                  546,488
      4,895,000   Citicorp                                               551,299
        200,000   First Bank System, Inc.                                 15,350
        100,000   First Union Corp.                                        8,400
      4,000,000   HSBC Holdings plc ORD                                  101,206
        700,000   Mellon Bank Corp.                                       58,187
      3,900,000   NationsBank Corp.                                      235,463
                                                                    ------------
                                                                       2,101,718
                                                                    ------------
BIOTECHNOLOGY -- 1.3%
      3,600,000   Amgen Inc.                                             211,725
        800,000   Elan Corp., plc ADR(1)                                  27,200
                                                                    ------------
                                                                         238,925
                                                                    ------------
BROADCASTING & MEDIA -- 0.8%
      1,700,000   Evergreen Media Corporation(1)(2)                       54,931
      2,200,000   Time Warner Inc.                                        99,000
                                                                    ------------
                                                                         153,931
                                                                    ------------
CHEMICALS & RESINS -- 0.4%
      1,375,000   Praxair, Inc.                                           70,984
                                                                    ------------
COMMUNICATIONS EQUIPMENT -- 4.5%
      5,305,000   Lucent Technologies, Inc.                              313,658
      5,370,000   Motorola Inc.                                          307,432
      1,450,000   Nokia Corp. Cl A ADR                                    93,706
      1,200,000   QUALCOMM Inc.(1)                                        55,950
      1,800,000   Tellabs, Inc.(1)                                        71,663
                                                                    ------------
                                                                         842,409
                                                                    ------------



Shares                          ($ in Thousands)                           Value
- --------------------------------------------------------------------------------
COMMUNICATIONS SERVICES -- 3.9%
        400,000   Alcatel Alsthom Compagnie Generale
                      d'Electricite ORD                              $    44,547
      3,450,000   Telecomunicacoes Brasileiras
                      S.A. ADR                                           395,888
      1,500,000   Telefonos de Mexico, S.A. ADR                           61,875
      9,600,000   Worldcom Inc.(1)                                       229,800
                                                                    ------------
                                                                         732,110
                                                                    ------------
COMPUTER PERIPHERALS -- 4.3%
         700,000  Applied Magnetics Corp(1)                               17,587
      1,400,000   Cisco Systems Inc.(1)                                   72,538
      3,050,000   EMC Corp. (Mass.)(1)                                   110,944
      6,600,000   Seagate Technology, Inc.(1)(2)                         302,775
      2,600,000   Storage Technology Corp.(1)(2)                          91,325
      3,500,000   Western Digital Corp.(1)(2)                            215,688
                                                                    ------------
                                                                         810,857
                                                                    ------------
COMPUTER SOFTWARE & SERVICES -- 5.3%
      3,801,000   America Online Inc.(1)                                 171,520
      4,522,400   BMC Software, Inc.(1)(2)                               195,311
      2,400,000   Electronics for Imaging, Inc.(1)                        93,900
      1,250,000   McAfee Associates, Inc.(1)                              69,687
      1,960,000   Microsoft Corp.(1)                                     238,262
      2,900,000   Oracle Systems Corp.(1)                                115,456
      2,650,000   Parametric Technology Corp.(1)                         119,747
        179,000   Sterling Commerce, Inc.(1)                               4,632
                                                                    ------------
                                                                       1,008,515
                                                                    ------------
COMPUTER SYSTEMS -- 7.1%
      1,450,000   Compaq Computer Corp.(1)                               123,794
      5,400,000   Dell Computer Corp.(1)                                 451,912
      1,413,500   Hewlett-Packard Co.                                     74,209
      1,700,000   International Business Machines Corp.                  273,275
     14,537,800   Sun Microsystems, Inc.(1)(2)                           418,870
                                                                    ------------
                                                                       1,342,060
                                                                    ------------
CONSUMER PRODUCTS -- 4.2%
        972,800   Colgate-Palmolive Co.                                  107,981
      3,500,000   Gillette Company                                       297,500
      2,560,000   Procter & Gamble Co. (The)                             321,920
        700,000   Ralston Purina Co.                                      57,663
                                                                    ------------
                                                                         785,064
                                                                    ------------
See Notes to Financial Statements


8   Ultra                                           American Century Investments



                             SCHEDULE OF INVESTMENTS
                                      ULTRA


APRIL 30, 1997 (UNAUDITED)
Shares                          ($ in Thousands)                           Value
- --------------------------------------------------------------------------------
DIVERSIFIED COMPANIES -- 2.9%
      4,750,000   General Electric Co.                              $    526,656
      3,250,000   Grupo Carso S.A. de CV Cl A1 ORD                        18,810
        110,000   Honeywell Inc.                                           7,769
                                                                    ------------
                                                                         553,235
                                                                    ------------
ELECTRICAL & ELECTRONIC
COMPONENTS -- 11.6%
        414,500   ASM Lithography Holding NV(1)                           32,979
         50,000   ASM Lithography Holding NV ORD(1)                        3,739
      1,150,000   Advanced Micro Devices, Inc.(1)                         48,875
      4,745,000   Altera Corp.(1)(2)                                     235,174
      3,069,000   Analog Devices, Inc.(1)                                 82,096
      5,750,000   Applied Materials, Inc.(1)                             315,172
      1,000,000   ESS Technology, Inc.(1)                                 13,688
      3,835,000   Intel Corp.                                            587,234
      7,000,000   LSI Logic Corp.(1)(2)                                  267,750
      1,950,000   Maxim Integrated Products, Inc.(1)                     102,984
      2,100,000   Micron Technology, Inc.                                 74,025
      2,250,000   National Semiconductor Corp.(1)                         56,250
        600,000   Rockwell International Corp.                            39,900
        500,000   Teradyne, Inc.(1)                                       16,375
      3,200,000   Texas Instruments Inc.                                 285,600
      1,400,000   VLSI Technology, Inc.(1)                                27,738
                                                                    ------------
                                                                       2,189,579
                                                                    ------------
ENERGY (PRODUCTION & MARKETING) -- 1.3%
        300,000   British Petroleum Co. p.l.c. ADR                        41,287
        725,000   Cooper Cameron Corp.(1)                                 51,656
      4,700,000   Global Marine, Inc.(1)                                  94,588
      2,000,000   Noble Drilling Corp.(1)                                 34,750
        475,000   Williams Companies, Inc. (The)                          20,841
                                                                    ------------
                                                                         243,122
                                                                    ------------
ENERGY (SERVICES) -- 1.5%
      2,850,000   Baker Hughes Inc.                                       98,325
      1,700,000   Schlumberger Ltd.                                      188,275
                                                                    ------------
                                                                         286,600
                                                                    ------------
ENVIRONMENTAL SERVICES -- 0.2%
      1,550,000   Republic Industries, Inc.(1)                            38,459
                                                                    ------------
FINANCIAL SERVICES -- 5.0%
      2,100,000   American Express Credit Corp.                          138,337
      3,600,000   Associates First Capital Corp.                         184,500



Shares                          ($ in Thousands)                           Value
- --------------------------------------------------------------------------------
      6,750,000   Federal Home Loan
                     Mortgage Corporation                           $    215,156
      2,950,000   Federal National Mortgage Association                  121,319
        460,000   Franklin Resources, Inc.                                27,198
      1,000,000   Household International, Inc.                           88,000
      1,945,000   ING Groep N.V. ORD                                      76,480
      3,000,000   MBNA Corp.                                              99,000
                                                                    ------------
                                                                         949,990
                                                                    ------------
FOOD & BEVERAGE -- 0.8%
      1,733,000   Coca-Cola Company (The)                                110,262
        962,100   Heinz (H.J.) Co.                                        39,927
                                                                    ------------
                                                                         150,189
                                                                    ------------
HEALTHCARE -- 1.9%
      5,000,000   Healthsouth Rehabilitation Corp.(1)                     98,750
      1,950,000   Oxford Health Plans, Inc.(1)                           128,334
      2,600,000   United HealthCare Corp.                                126,425
                                                                    ------------
                                                                         353,509
                                                                    ------------
INSURANCE -- 2.1%
      1,150,000   Aetna Life and Casualty Co.                            104,794
      1,150,000   Allstate Corp.                                          75,325
      1,800,000   Chubb Corp. (The)                                      103,950
      1,400,000   ITT Hartford Group, Inc.                               104,300
                                                                    ------------
                                                                         388,369
                                                                    ------------
LEISURE -- 2.2%
      1,970,000   Disney (Walt) Co.                                      161,540
      8,150,000   Hilton Hotels Corporation                              220,050
        500,000   Marriott International, Inc.                            27,625
                                                                    ------------
                                                                         409,215
                                                                    ------------
MEDICAL EQUIPMENT & SUPPLIES -- 0.4%
        600,000   Medtronic, Inc.                                         41,550
      1,250,000   US Surgical Corp.                                       42,813
                                                                    ------------
                                                                          84,363
                                                                    ------------
OFFICE EQUIPMENT -- 1.0%
      3,000,000   Xerox Corp.                                            184,500
                                                                    ------------
PAPER & FOREST PRODUCTS -- 0.8%
      2,900,000   Kimberly-Clark Corp.                                   148,625
                                                                    ------------
PHARMACEUTICALS -- 16.9%
        623,000   Abbott Laboratories                                     38,003
      3,500,000   American Home Products Corp.                           231,875


See Notes to Financial Statements


Semiannual Report                                                     Ultra    9



                             SCHEDULE OF INVESTMENTS
                                      ULTRA




APRIL 30, 1997 (UNAUDITED)
Shares                          ($ in Thousands)                           Value
- --------------------------------------------------------------------------------
        505,800   Bristol-Myers Squibb Co.                           $    33,130
      9,560,000   Johnson & Johnson                                      585,550
      3,750,000   Lilly (Eli) & Co.                                      329,531
      8,100,000   Merck & Co., Inc.                                      733,050
        144,000   Novartis ORD                                           190,107
      5,900,000   Pfizer, Inc.                                           566,400
      2,850,000   Teva Pharmaceutical
                     Industries Ltd. ADR(2)                              143,925
      3,350,000   Warner-Lambert Co.                                     328,300
                                                                    ------------
                                                                       3,179,871
                                                                    ------------
RESTAURANTS -- 0.8%
      2,700,000   McDonald's Corp.                                       144,788
                                                                    ------------
RETAIL (APPAREL) -- 0.3%
        900,000   NIKE, Inc.                                              50,625
                                                                    ------------
RETAIL (FOOD & DRUG) -- 0.3%
        850,000   Koninklijke Ahold NV ORD                                58,108
         55,000   Safeway Inc.(1)                                          2,454
        123,000   Walgreen Co.                                             5,658
                                                                    ------------
                                                                          66,220
                                                                    ------------
RETAIL (GENERAL MERCHANDISE) -- 0.5%
      2,500,000   Kmart Corp.(1)                                          34,063
      1,275,000   Sears, Roebuck & Co.                                    61,200
                                                                    ------------
                                                                          95,263
                                                                    ------------
RETAIL (SPECIALTY) -- 0.5%
      3,000,000   Starbucks Corp.(1)(2)                                   89,250
                                                                    ------------
TOBACCO -- 1.2%
     12,000,000   B.A.T. Industries PLC ORD                              101,664
      3,281,700   Philip Morris Companies Inc.                           129,217
                                                                    ------------
                                                                         230,881
                                                                    ------------

TOTAL COMMON STOCKS -- 97.7%                                          18,412,375
     (Cost $14,164,062)                                             ------------


Principal Amount      ($ in Thousands)Value
- --------------------------------------------------------------------------------
- --------------------------------------------------------------------------------
TEMPORARY CASH INVESTMENTS(3)
- --------------------------------------------------------------------------------
     $36,000 par value FFCB Discount Notes,
     5.33%-5.38%, 5/8/97 through 5/15/97                             $    35,938

     $270,000 par value FHLMC Discount Notes,
     5.35%-5.43%, 5/6/97 through 6/9/97                                  269,228

     $128,000 par value FNMA Discount Notes,
     5.38%-5.40%, 5/5/97 through 6/11/97                                 127,444
                                                                    ------------

TOTAL TEMPORARY CASH
INVESTMENTS-- 2.3%                                                       432,610
   (Cost $432,610)                                                  ------------

TOTAL INVESTMENT SECURITIES-- 100.0%                                 $18,844,985
   (Cost $14,596,672)                                               ============
     


FORWARD FOREIGN CURRENCY CONTRACTS
- --------------------------------------------------------------------------------
           Contracts           Settlement                         Unrealized
            to Sell               Dates            Value          Gain (Loss)
- --------------------------------------------------------------------------------
     55,347,296    GBP           6/30/97          $89,901           $(106)
     177,520,000   FRF           6/30/97          30,587               7
     260,706,810   NLG           6/30/97         134,576              317
     217,152,000   CHF           6/30/97          148,605             389
                                               ------------      ------------
                                                 $403,669            $607
     (Value on Settlement Date $404,276)       ============      ============



NOTES TO SCHEDULE OF INVESTMENTS

ADR = American Depositary Receipt
CHF = Swiss Franc
FFCB = Federal Farm Credit Bank
FHLMC = Federal Home Loan Mortgage  Corporation 
FNMA = Federal National Mortgage Association 
FRF = French Franc 
GBP = British Pound 
NLG = Netherlands Guilder 
ORD = Foreign Ordinary Share
(1)  Non-income producing.
(2)  Affiliated  Company:  represents  ownership  of at least  5% of the  voting
     securities of the issuer and is, therefore,  an affiliate as defined in the
     Investment  Company  Act  of  1940.  (See  Note  5 in  Notes  to  Financial
     Statements for a summary of  transactions  for each issuer who is or was an
     affiliate at or during the six months ended April 30, 1997.)
(3)  The  rates  for U.S.  Government  Agency  discount  notes  are the yield to
     maturity at April 30, 1997.


See Notes to Financial Statements


10   Ultra                                          American Century Investments

<TABLE>
<CAPTION>
                                      VISTA

TOTAL RETURNS AS OF APRIL 30, 1997
- ---------------------------------------------------------------------------------------------------------------------------------
                                                                             AVERAGE ANNUAL RETURNS
<S>                               <C>              <C>              <C>               <C>               <C>             <C>   
                               --------------------------------------------------------------------------------------------------
                                6 MONTHS          1 YEAR            3 YEARS          5 YEARS          10 YEARS       LIFE OF FUND
- ---------------------------------------------------------------------------------------------------------------------------------
INVESTOR CLASS (inception 11/25/83)
- ---------------------------------------------------------------------------------------------------------------------------------
     Vista.....................  -20.79%          -23.56%           11.02%            8.91%             8.37%           11.46%
     Russell 2500 Growth.......  -3.73%           -6.98%            13.08%           12.07%             9.94%             --(1)

- ---------------------------------------------------------------------------------------------------------------------------------
ADVISOR CLASS (inception 10/2/96)
- ---------------------------------------------------------------------------------------------------------------------------------
     Vista.....................  -20.89%............................................................................... -26.47%
     Russell 2500 Growth.......  -3.73%................................................................................-6.73%(2)

- ---------------------------------------------------------------------------------------------------------------------------------
INSTITUTIONAL CLASS (inception 11/14/96)
- ---------------------------------------------------------------------------------------------------------------------------------
     Vista............................................................................................................. -21.02%
     Russell 2500 Growth...............................................................................................-7.14%(3)
</TABLE>

(1)  Not available. Index data begins in 1986.

(2)  For the period from  9/30/96 (the date  nearest the class's  inception  for
     which data are available) to 4/30/97.

(3)  For the period from  11/30/96  (the date nearest the class's  inception for
     which data are available) to 4/30/97.

See  pages  32,  36  and  37 for  more  information  about  share  classes,  the
comparative indices and returns.


[line graph - data below]

GROWTH OF $10,000 OVER 10 YEARS (Investor Class)
- --------------------------------------------------------------

                                                                  RUSSELL 2500
                  VISTA                    NASDAQ                 GROWTH INDEX
             ---------------           ---------------           ---------------
DATE           ACCT VALUE                ACCT VALUE                ACCT VALUE
- --------------------------------------------------------------------------------
4/30/87         $10,000                   $10,000                    $10,000
4/30/88          $7,792                    $9,077                     $9,024
4/30/89          $9,410                   $10,233                    $10,387
4/30/90         $10,828                   $10,054                    $10,786
4/30/91         $12,400                   $11,601                    $12,604
4/30/92         $14,582                   $13,850                    $14,591
4/30/93         $15,082                   $15,831                    $15,596
4/30/94         $16,322                   $17,564                    $17,838
4/30/95         $19,824                   $20,200                    $19,922
4/30/96         $29,225                   $28,495                    $27,730
4/30/97         $22,340                   $30,175                    $25,793



Past  performance  does not  guarantee  future  results.  Investment  return and
principal  value will fluctuate,  and redemption  value may be more or less than
original  cost.  Data quoted is for Investor Class only;  performance  for other
classes will vary due to differences  in fee  structures  (see the Total Returns
table above).

The line representing  Vista's total return includes operating expenses (such as
transaction  costs and  management  fees) that reduce  returns,  while the total
return lines of the Nasdaq and Russell 2500 Growth indices do not.



PORTFOLIO AT A GLANCE
- ------------------------------------------------------------------------
                                            4/30/97           10/31/96
Number of Companies                         60                61
Median Price/Earnings Ratio                 30.9              53.9
Portfolio Turnover                          49%(1)            91%(2)
Expense Ratio (for Investor Class)        1.00%(3)          0.99%


(1) Six months ended 4/30/97.

(2) Year ended 10/31/96.

(3) Annualized.



Semiannual Report                                                    Vista    11



                                      VISTA


Management Q & A

An interview with Glenn Fogle and John Seitzer,  portfolio managers on the Vista
management team.

HOW DID THE FUND PERFORM DURING THE SIX MONTHS ENDED APRIL 30?

Vista's  total  return of -20.79%  represented  one of the  steepest  short-term
declines in the fund's 13-year history. The fund's negative performance resulted
from the generally  unfavorable  investment  environment  for mid- and small-cap
growth  stocks,  compounded by our focus on the most rapidly  growing  companies
within that sector of the equity market.  Our concentration on these businesses,
hardest  hit by the  market's  turbulence,  caused  the fund to suffer a greater
decline than benchmark market indices.

When reflecting on this six-month  performance,  it's important to remember that
we manage  Vista  aggressively  for  long-term  returns.  As a result,  the fund
historically  has been  very  volatile,  sometimes  underperforming  the  market
dramatically and other times  significantly  outperforming  it. (The graph below
shows Vista's varied  performance over short-term  periods.) Vista has rebounded
sharply from similar performance  downswings.  We cannot predict when this might
occur,  but we can assure  investors that we are accustomed to managing  through
periods of intense market volatility as well as the peaks and valleys in Vista's
performance resulting from our investment style.

HOW DID MID-CAP AND SMALL-CAP GROWTH STOCKS PERFORM?

The  mid-cap  and  small-cap  growth  stocks  that  comprise  Vista's  portfolio
significantly  underperformed the S&P 500. Mid-cap growth stocks, as measured by
the S&P  400/BARRA  Growth  Index,  posted a 4.66% total  return for the period,
while the Russell 2500 Growth Index,  which  represents a blend of small-cap and
mid-cap stocks, posted a -3.73% total return.


[bar graph - data below]

VISTA'S ONE-YEAR RETURNS OVER 10 YEARS(1) (Periods ended April 30)
- --------------------------------------------------------------------------

                                               RUSSELL 2500
                         VISTA                 GROWTH INDEX
                    ---------------           ---------------
DATE                    RETURN                    RETURN
- --------------------------------------------------------------------------
4/30/88                -22.08%                    -9.76%
4/30/89                 20.76%                    15.11%
4/30/90                 15.07%                     3.84%
4/30/91                 14.52%                    16.85%
4/30/92                 17.60%                    15.77%
4/30/93                  3.43%                     6.88%
4/30/94                  8.22%                    14.37%
4/30/95                 21.46%                    11.68%
4/30/96                 47.42%                    39.19%
4/30/97                -23.56%                    -6.98%




This chart  illustrates  the fund's  returns over the past 10 years and compares
them with the returns of the Russell 2500 Growth  Index.  Vista's  total returns
include  operating  expenses,  while the Russell 2500 Growth Index's  returns do
not.  See  page  36 for a  description  of the  index.  Past  performance  is no
guarantee of future results

(1) Investor Class.


12   Vista                                          American Century Investments



                                      VISTA


WHY WAS THE FUND'S PERFORMANCE BENCHMARK CHANGED FROM THE NASDAQ COMPOSITE INDEX
TO THE RUSSELL 2500 GROWTH INDEX?

The benchmark  should  resemble the holdings in Vista's  portfolio as closely as
possible.  The  problem  with the Nasdaq  index is that it  contains a number of
large-cap companies such as Microsoft and Intel that have market capitalizations
in excess of $100  billion  and do not appear in Vista's  portfolio.  The Nasdaq
index's  performance can be greatly skewed by these heavyweight  companies.  The
challenge was to find an index that reflects Vista's blend of small-cap (smaller
than $1 billion) and mid-cap ($1 billion to $5 billion)  holdings.  We chose the
Russell  2500  Growth  Index,  which has an  average  market  capitalization  of
approximately  $600 million.  This is smaller than Vista's $1.8 billion  average
market  capitalization at the end of the period, but other characteristics (such
as growth rates and valuation  measures) make this index a better benchmark than
other mid-cap indices, in our opinion.

WHY DID VISTA'S  PERFORMANCE  DIFFER SO MARKEDLY  FROM THAT OF THE RUSSELL  2500
GROWTH INDEX?

Unlike an index fund, Vista makes no attempt to match any benchmark returns over
short-term  periods.  In  seeking  superior  long-term  returns,  the fund  owns
companies  that have much  higher  growth  rates than  those in the index.  As a
result,  the fund  usually  appears more  expensive  than the index on valuation
measures.  Over time, we expect the exceptional earnings growth potential of the
stocks Vista owns to more than offset the premium  paid to buy these  companies.
In  the  short  run,  however,  the  fund  can be  very  volatile  and  markedly
underperform the index. Our management of the fund has remained  consistent with
our  long-held  investment  discipline.  We bought and now own some great growth
businesses.  Unfortunately,  as sometimes  happens,  the prices of many of those
stocks have fallen since we acquired them, in spite of strong earnings  reports.
We are prepared to retain the shares of good businesses that meet our investment
standards even if they fall  temporarily out of favor and their share prices lag
for a while.  While the past is no guarantee of the future, our experience tells
us that over the long term we'll be rewarded with higher share prices.



TOP TEN HOLDINGS                           % of fund investments
- --------------------------------------------------------------------
                                         As of             As of
                                         4/30/97          10/31/96
McAfee Associates, Inc.                   4.0%              2.7%
Dura Pharmaceuticals, Inc.                3.7%              3.4%
HFS, Inc.                                 3.6%              5.8%
USA Waste Services, Inc.                  3.4%              2.6%
Comverse Technology, Inc.                 3.2%              2.6%
PairGain Technologies, Inc.               3.0%              6.7%
HBO & Co.                                 2.9%              4.0%
United Waste Systems, Inc.                2.9%              1.7%
Sanmina Corp.                             2.7%              0.8%
U.S. Filter Corp.                         2.3%               --




TOP FIVE INDUSTRIES                        % of fund investments
- --------------------------------------------------------------------
                                         As of             As of
                                         4/30/97          10/31/96
Computer Software & Services              13.0%             20.3%
Communications Equipment                  10.4%             13.1%
Business Services & Supplies              10.0%             15.4%
Energy (Services)                         10.0%              --
Electrical & Electronic Components        7.0%              2.0%




Semiannual Report                                                    Vista    13



                                      VISTA


CAN YOU GIVE INVESTORS ENCOURAGEMENT ABOUT THE FUND'S PERFORMANCE?

There are several  factors that encourage us about the prospects for Vista.  The
number of new stock offerings (IPOs) has declined  dramatically in 1997 compared
to the prior two years,  stemming the flood of new issues that were crowding the
market.  The  sell-off in mid- and  small-cap  growth  stocks has brought  their
valuation relative to large-cap stocks down to historically low levels. Finally,
the  companies  that  Vista  owns  continue  to report  dynamic  growth in their
revenues and earnings.

In terms of its investment philosophy and objectives, Vista is still essentially
the same fund it was two years ago when it was  generating  high returns.  We've
stuck to our basic  investment  discipline,  even though it's  currently  out of
favor. We've remained focused on long-term results.  The stock market,  like the
economy, moves in cycles. Periods such as the recent one, when uncertainty about
the  strength  of the  economy and the  direction  of interest  rates make stock
investors more  conservative,  are normal.  Eventually,  market sentiment should
shift again, and when it does we would expect the  fast-growing  stocks owned in
Vista to reward investors for their patience.

WHAT CHANGES DID YOU MAKE IN THE FUND'S INVESTMENT STRATEGY OR HOLDINGS?

We still own a  significant  number of  technology  stocks  because  the  sector
continues to produce high and rising earnings growth rates. However,  within the
technology group we shifted our focus to somewhat  stronger  companies with more
secure  businesses.  Because the  sell-off  in  technology  shares hit  industry
leaders as well as less established  companies,  we were able to build positions
in several  more-seasoned,  high-quality  names. These are the stocks we believe
will rebound strongly when the market once again favors fast-growing companies.

Apart from companies with unique niches in the computer  software  industry such
as HBO & Company and McAfee Associates (two of the fund's top ten holdings as of
April 30), we made a strategic  decision to reduce our software holdings because
of  increasing  competition  and low barriers to entry.  We sold a number of our
holdings in business  services for similar reasons.  We also cut back on some of
our largest holdings such as HFS, Inc. and PairGain  Technologies,  Inc. because
we felt our positions were becoming too concentrated.

On the other hand,  we increased  our holdings in  semiconductor  companies  and
circuit board manufacturers. Sanmina Corporation and Jabil Circuit, Inc. are two
of  the  leading  contract  circuit  manufacturers  in  the  world.  Maintaining
electronics  manufacturing  capacity requires a substantial  capital investment.
There is a growing trend among computer and telecommunications companies such as
Hewlett-Packard  and Cisco Systems to  subcontract  this activity to specialists
such as Sanmina and Jabil Circuit,  which are among only a handful of firms that
can provide global state-of-the art production capability.

We also  bought  energy  services  companies  after oil and  natural  gas prices
dropped this winter.  As a result of years of fundamental  restructuring in this
industry,  we're seeing  accelerating  earnings that we believe are sustainable.
Here, as in other industries,  technology is driving increased productivity. For
example, geologists now routinely analyze three-dimensional seismic data to find
oil and natural gas below the ocean floor.  With this more  accurate view of the
size and location of undersea  reserves,  energy  companies can drill profitable
wells in locations that were previously economically unfeasible.



14   Vista                                          American Century Investments



                                      VISTA


WHAT DO YOU THINK WILL CAUSE THE MARKET FOR MID- AND SMALL-CAP  GROWTH STOCKS TO
TURN AROUND?

The  outperformance  of large-cap stocks over the past year has coincided with a
period of better-than-average (and better-than-expected)  earnings growth, which
we think is attributable to the  surprisingly  robust economy.  For the past two
years the largest stocks in the S&P 500 index have seemingly offered  everything
an investor could desire:  strong earnings growth,  above average  returns,  low
volatility and superior  liquidity.  To some extent,  the extraordinary  returns
have also been self-perpetuating, as momentum-following market participants have
sold  their  underperforming  stocks  (often  small-cap)  in  order  to buy  the
large-cap leaders.

We  think  that a  change  in  market  leadership  will  probably  begin  with a
deteriorating outlook for earnings, and that change may not be too far away. The
economy is finally showing signs of slower growth, and the Federal Reserve seems
intent on ensuring that trend. Slower growth, higher interest rates and a strong
dollar all put pressure on the earnings growth rates of larger  companies.  With
the profit margins at large-cap  companies  already at historically high levels,
it seems  probable that their  earnings  growth rates will decline over the next
few quarters.  Some smaller  companies will suffer the same  deterioration,  but
those that can buck the trend  should  attract  growth-oriented  investors.  The
inexpensive  relative  valuation  of  mid-  and  small-cap  stocks  should  also
contribute to their recovery.

The year-long  divergence between large- and smaller-cap stocks is very unusual,
which  suggests  the  strong  possibility  of  a  mid-  and  small-cap  rebound.
Unfortunately  there is no telling  precisely  when this might happen or to what
degree.  We avoid trying to time the market (and we  discourage  fund  investors
from doing so) because market trends can reverse  abruptly and without  warning.
Instead,  we concentrate on keeping the fund well positioned with investments in
good, growing businesses with the strongest  fundamental outlook we can find. We
don't have any  control  over the timing of how the  market  reacts,  but we can
control our investment strategy and goals.

EDITOR'S NOTE ON JUNE 6, 1997:
SINCE APRIL 30, VISTA'S SHARE VALUE HAS RISEN BY 15%, COMPARED TO AN INCREASE OF
7% IN THE S&P 500. THE CHANGE IN MARKET SENTIMENT  REGARDING SMALL COMPANIES MAY
HAVE BEGUN.


Semiannual Report                                                    Vista    15



                             SCHEDULE OF INVESTMENTS
                                      VISTA


APRIL 30, 1997 (UNAUDITED)
Shares                          ($ in Thousands)                           Value
- --------------------------------------------------------------------------------
- --------------------------------------------------------------------------------
COMMON STOCKS
- --------------------------------------------------------------------------------
BIOTECHNOLOGY -- 4.9%
        627,900   BioChem Pharma Inc.(1)                             $    11,302
        162,000   Biogen, Inc.(1)                                          5,204
      1,100,000   Centocor, Inc.(1)                                       31,006
        540,000   IDEC Pharmaceuticals Corp.(1)(2)                         9,652
        250,000   Protein Design Labs, Inc.(1)                             6,266
        460,000   Vertex Pharmaceuticals, Inc.(1)                         14,548
                                                                    ------------
                                                                          77,978
                                                                    ------------
BUSINESS SERVICES & SUPPLIES -- 10.0%
      1,800,000   AccuStaff, Inc.(1)                                      32,850
        700,000   Corestaff, Inc.(1)                                      12,119
      1,000,000   Corrections Corp. of America(1)                         32,625
        457,600   National Data Corp.                                     17,160
        537,500   Quintiles Transnational Corp.(1)                        27,345
      1,200,000   U.S. Filter Corp.(1)                                    36,450
                                                                    ------------
                                                                         158,549
                                                                    ------------
COMMUNICATIONS EQUIPMENT -- 10.4%
      1,512,500   Brightpoint, Inc.(1)(2)                                 33,086
        205,500   Cable Design Technologies Corp.(1)                       3,879
      1,300,000   Comverse Technology, Inc.(1)(2)                         51,350
      1,050,000   P-COM, Inc.(1)(2)                                       29,794
      1,820,000   PairGain Technologies, Inc.(1)(2)                       47,206
                                                                    ------------
                                                                         165,315
                                                                    ------------
COMPUTER PERIPHERALS -- 4.5%
        710,000   Applied Magnetics Corp.(1)                              17,839
        515,000   Quantum Corp.(1)                                        21,469
        715,000   Seagate Technology, Inc.(1)                             32,801
                                                                    ------------
                                                                          72,109
                                                                    ------------
COMPUTER SOFTWARE & SERVICES -- 13.0%
        215,000   Acxiom Corp.(1)                                          2,849
        565,000   Aspen Technology, Inc.(1)(2)                            17,338
      1,420,000   Cognos Incorporated(1)(2)                               36,032
        875,000   HBO & Co.                                               46,758
      1,400,000   Hyperion Software Corp.(1)(2)                           22,575
      1,130,000   McAfee Associates, Inc.(1)                              62,998
      1,300,000   Rational Software Corp.(1)(2)                           17,956
                                                                    ------------
                                                                         206,506
                                                                    ------------

Shares                          ($ in Thousands)                           Value
- --------------------------------------------------------------------------------
EDUCATION -- 1.4%
        800,000   Apollo Group Inc. Cl A(1)                          $    21,550
                                                                    ------------
ELECTRICAL & ELECTRONIC
COMPONENTS -- 7.0%
        531,100   Jabil Circuit, Inc.(1)                                  25,659
        450,000   Lattice Semiconductor Corp.(1)                          25,200
        850,000   Sanmina Corp.(1)(2)                                     42,553
         74,600   Solectron Corp.(1)                                       4,280
        450,000   Vitesse Semiconductor Corp.(1)                          14,259
                                                                    ------------
                                                                         111,951
                                                                    ------------
ENERGY (SERVICES) -- 10.0%
        280,000   Atwood Oceanics, Inc.(1)                                17,255
        244,000   Diamond Offshore Drilling(1)                            15,707
      1,620,000   Marine Drilling Companies, Inc.(1)                      25,717
        800,000   Petroleum Geo-Services A/S ADR(1)                       30,800
        725,000   Smith International, Inc.(1)                            34,347
        860,000   Tidewater Inc.                                          34,508
                                                                    ------------
                                                                         158,334
                                                                    ------------
ENVIRONMENTAL SERVICES -- 6.3%
      1,650,000   USA Waste Services, Inc.(1)                             54,037
      1,368,000   United Waste Systems, Inc.(1)                           46,085
                                                                    ------------
                                                                         100,122
                                                                    ------------
HEALTHCARE -- 6.3%
        317,500   CRA Managed Care, Inc.(1)                               11,271
      1,175,000   Health Management Associates, Inc.(1)                   31,431
        330,000   OccuSystems, Inc.(1)                                     6,744
        380,000   Oxford Health Plans, Inc.(1)                            25,010
      1,000,000   Tenet Healthcare Corp.(1)                               26,000
                                                                    ------------
                                                                         100,456
                                                                    ------------
LEISURE -- 4.3%
        970,000   HFS, Inc.(1)                                            57,472
        390,700   Regal Cinemas, Inc.(1)                                  10,671
                                                                    ------------
                                                                          68,143
                                                                    ------------
MACHINERY & EQUIPMENT -- 2.3%
        825,800   Diebold, Inc.                                           27,664
        250,000   Dynatech Corp.(1)                                        8,688
                                                                    ------------
                                                                          36,352
                                                                    ------------
METALS & MINING -- 1.1%
        650,000   Titanium Metals Corporation(1)                          16,859
                                                                    ------------



See Notes to Financial Statements


16   Vista                                          American Century Investments



                             SCHEDULE OF INVESTMENTS
                                      VISTA


APRIL 30, 1997 (UNAUDITED)
Shares/Principal Amount         ($ in Thousands)                           Value
- --------------------------------------------------------------------------------
PHARMACEUTICALS -- 6.8%
      2,000,000   Dura Pharmaceuticals, Inc.(1)(2)                   $    58,125
        728,000   Jones Medical Industries, Inc.                          25,889
        945,000   Medicis Pharmaceutical Corp.(1)(2)                      23,212
                                                                    ------------
                                                                         107,226
                                                                    ------------
RETAIL (APPAREL) -- 2.4%
        750,000   Jones Apparel Group, Inc.(1)                            31,313
        270,000   Ross Stores, Inc.                                        7,628
                                                                    ------------
                                                                          38,941
                                                                    ------------
RETAIL (GENERAL MERCHANDISE) -- 1.0%
        380,000   Consolidated Stores Corp.(1)                            15,200
                                                                    ------------
RETAIL (SPECIALTY) -- 2.5%
      1,300,000   Corporate Express, Inc.(1)                              12,837
        235,000   Fastenal Company                                         9,121
        830,000   Hollywood Entertainment Corp.(1)                        17,586
                                                                    ------------
                                                                          39,544
                                                                    ------------

TOTAL COMMON STOCKS-- 94.2%                                            1,495,135
     (Cost $1,281,258)                                              ============



- --------------------------------------------------------------------------------
TEMPORARY CASH INVESTMENTS(3)
- --------------------------------------------------------------------------------
     $50,000 par value FHLMC Discount Note,
     5.36%, 5/2/97                                                        49,993

     Repurchase Agreement, Goldman Sachs
     & Co., Inc., (U.S. Treasury obligations),
     in a joint trading account at 5.29%,
     dated 4/30/97, due 5/1/97
     (Delivery value $42,506)                                             42,500
                                                                    ------------

TOTAL TEMPORARY CASH
INVESTMENTS-- 5.8%                                                        92,493
   (Cost $92,493)                                                   ------------

TOTAL INVESTMENT SECURITIES-- 100.0%                                  $1,587,628
     (Cost $1,373,751)                                              ============




NOTES TO SCHEDULE OF INVESTMENTS

ADR = American Depositary Receipt
FHLMC = Federal Home Loan Mortgage Corporation
(1)  Non-income producing.
(2)  Affiliated  Company:  represents  ownership  of at least  5% of the  voting
     securities of the issuer and is, therefore,  an affiliate as defined in the
     Investment  Company  Act  of  1940.  (See  Note  5 in  Notes  to  Financial
     Statements for a summary of  transactions  for each issuer who is or was an
     affiliate at or during the six months ended April 30, 1997.)
(3)  The  rates  for U.S.  Government  Agency  discount  notes  are the yield to
     maturity at April 30, 1997.


See Notes to Financial Statements


Semiannual Report                                                    Vista    17


<TABLE>
<CAPTION>
                      STATEMENTS OF ASSETS AND LIABILITIES



APRIL 30, 1997 (UNAUDITED)                                                              ULTRA             VISTA

- ------------------------------------------------------------------------------------------------------------------------
ASSETS                                                                         ($ in Thousands Except Per-Share Amounts)
- ------------------------------------------------------------------------------------------------------------------------
<S>                                                                                       <C>                <C>  
Investment securities, at value (identified cost of $14,596,672
     and $1,373,751, respectively) (Note 3)......................................... $18,844,985        $1,587,628
Cash     ...........................................................................      12,048             2,095
Receivable for forward foreign currency exchange contracts..........................         713                --
Receivable for investments sold.....................................................     279,145            27,602
Receivable for capital shares sold..................................................       1,216               440
Dividends and interest receivable...................................................      22,359                 6
                                                                                     ------------      ------------
                                                                                      19,160,466         1,617,771
                                                                                     ------------      ------------

- ------------------------------------------------------------------------------------------------------------------------
LIABILITIES
- ------------------------------------------------------------------------------------------------------------------------
Disbursements in excess of demand deposit cash......................................      19,719             3,281
Payable for forward foreign currency exchange contracts.............................         106                --
Payable for investments purchased...................................................     215,358            24,875
Payable for capital shares redeemed.................................................      18,894             1,113
Accrued management fees (Note 2)....................................................      14,867             1,323
Distribution fees payable (Note 2)..................................................           3                 1
Service fees payable (Note 2).......................................................           3                 1
Other liabilities...................................................................          43                 8
                                                                                     ------------      ------------
                                                                                         268,993            30,602
                                                                                     ------------      ------------

Net Assets.......................................................................... $18,891,473        $1,587,169
                                                                                     ============      ============

- ------------------------------------------------------------------------------------------------------------------------
NET ASSETS CONSIST OF:
- ------------------------------------------------------------------------------------------------------------------------
Capital (par value and paid in surplus)............................................. $12,188,420        $1,477,930
Undistributed net investment income (loss)..........................................       9,399            (7,534)
Accumulated undistributed net realized gain (loss) on investment
     and foreign currency transactions..............................................   2,444,631          (97,103)
Net unrealized appreciation on investments and translation
     of assets and liabilities in foreign currencies (Note 3).......................   4,249,023           213,876
                                                                                     ------------      ------------
                                                                                     $18,891,473        $1,587,169
                                                                                     ============      ============
Investor Class ($ and shares in full)
Net assets.......................................................................$18,873,513,420    $1,568,832,615
Shares outstanding.................................................................. 648,373,654       136,742,803
Net asset value per share...........................................................      $29.11            $11.47
Advisor Class ($ and shares in full)
Net assets.......................................................................... $17,856,877        $5,088,240
Shares outstanding .................................................................     614,327           444,136
Net asset value per share...........................................................      $29.07            $11.46
Institutional Class ($ and shares in full)
Net assets..........................................................................    $102,764       $13,248,422
Shares outstanding .................................................................       3,527         1,153,594
Net asset value per share...........................................................      $29.14            $11.48
</TABLE>

See Notes to Financial Statements


18   Statements of Assets and Liabilities           American Century Investments


<TABLE>
<CAPTION>
                            STATEMENTS OF OPERATIONS



FOR THE SIX MONTHS ENDED APRIL 30, 1997 (UNAUDITED)                                     ULTRA             VISTA
- ------------------------------------------------------------------------------------------------------------------------
INVESTMENT INCOME                                                                          ($ in Thousands)
- ------------------------------------------------------------------------------------------------------------------------
<S>                                                                                        <C>               <C>  
Income:
Dividends (net of foreign taxes withheld of $627 and $0, respectively)..............     $95,926              $618
Interest ...........................................................................       8,908             1,891
                                                                                     ------------      ------------
                                                                                         104,834             2,509
                                                                                     ------------      ------------

Expenses (Note 2):
Management fees.....................................................................      94,121            10,017
Distribution fees - Advisor Class...................................................          19                 7
Shareholder service fees - Advisor Class............................................          19                 7
Directors' fees and expenses........................................................         125                12
                                                                                     ------------      ------------
                                                                                          94,284            10,043
                                                                                     ------------      ------------

Net investment income (loss)........................................................      10,550            (7,534)
                                                                                     ------------      ------------

- ------------------------------------------------------------------------------------------------------------------------
REALIZED AND UNREALIZED GAIN (LOSS)
ON INVESTMENTS AND FOREIGN CURRENCY (NOTE 3)
- ------------------------------------------------------------------------------------------------------------------------
Net realized gain (loss) on:
Investments.........................................................................   2,454,966           (96,194)
Foreign currency transactions.......................................................      24,959                --
                                                                                     ------------      ------------
                                                                                       2,479,925           (96,194)
                                                                                     ------------      ------------

Change in net unrealized appreciation on:
Investments.........................................................................  (1,697,933)         (321,757)
Translation of assets and liabilities in foreign currencies.........................        (308)               --
                                                                                     ------------      ------------
                                                                                      (1,698,241)         (321,757)
                                                                                     ------------      ------------

Net realized and unrealized gain (loss) on investments..............................     781,684          (417,951)
                                                                                     ------------      ------------

Net Increase (Decrease) in Net Assets Resulting from Operations.....................    $792,234         $(425,485)
                                                                                     ============      ============
</TABLE>


See Notes to Financial Statements


Semiannual Report                                   Statements of Operations  19


<TABLE>
<CAPTION>
                       STATEMENTS OF CHANGES IN NET ASSETS


SIX MONTHS ENDED APRIL 30, 1997 (UNAUDITED)
AND YEAR ENDED OCTOBER 31, 1996                                   ULTRA                              VISTA

Increase (Decrease) in Net Assets                         1997              1996             1997              1996
- ------------------------------------------------------------------------------------------------------------------------
OPERATIONS                                                                      ($ in Thousands)
- ------------------------------------------------------------------------------------------------------------------------

<S>                                                   <C>              <C>               <C>              <C>      
Net investment income (loss).....................     $10,550          $(31,468)         $(7,534)         $(14,784)

Net realized gain (loss) on investments
     and foreign currency transactions...........    2,479,925        1,037,212          (96,194)           171,813

Change in net unrealized appreciation
     on investments and translation of assets
     and liabilities in foreign currencies.......  (1,698,241)          777,976         (321,757)          (24,182)
                                                  ------------      ------------     ------------      ------------
Net increase (decrease) in net assets
     resulting from operations...................     792,234         1,783,720         (425,485)           132,847
                                                  ------------      ------------     ------------      ------------

- ------------------------------------------------------------------------------------------------------------------------
DISTRIBUTIONS TO SHAREHOLDERS
- ------------------------------------------------------------------------------------------------------------------------
From net realized gains from investment transactions:

     Investor Class..............................  (1,044,610)         (673,603)        (168,259)         (111,473)

     Advisor Class...............................        (778)                --            (449)                --

     Institutional Class.........................        (547)                --            (225)                --

In excess of net realized gain:
     Investor Class..............................           --           (9,858)               --           (1,791)
                                                  ------------      ------------     ------------      ------------

Decrease in net assets from distributions........  (1,045,935)         (683,461)        (168,933)         (113,264)
                                                  ------------      ------------     ------------      ------------

- ------------------------------------------------------------------------------------------------------------------------
CAPITAL SHARE TRANSACTIONS (NOTE 4)
- ------------------------------------------------------------------------------------------------------------------------
Net increase (decrease) in net assets from
     capital share transactions..................      866,228        2,802,785          (99,891)           585,978
                                                  ------------      ------------     ------------      ------------


Net increase (decrease) in net assets............      612,527         3,903,044        (694,309)           605,561

- ------------------------------------------------------------------------------------------------------------------------
NET ASSETS
- ------------------------------------------------------------------------------------------------------------------------
Beginning of period..............................   18,278,946        14,375,902        2,281,478         1,675,917
                                                  ------------      ------------     ------------      ------------

End of period....................................  $18,891,473       $18,278,946       $1,587,169        $2,281,478
                                                  ============      ============     ============      ============

Undistributed net investment income (loss).......       $9,399                --         $(7,534)                --
                                                  ============      ============     ============      ============
</TABLE>

See Notes to Financial Statements


20   Statements of Changes in Net Assets            American Century Investments



                          NOTES TO FINANCIAL STATEMENTS

APRIL 30, 1997 (UNAUDITED)

1. ORGANIZATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

ORGANIZATION  -- American  Century  Mutual  Funds,  Inc.  (the  Corporation)  is
registered under the Investment  Company Act of 1940 as an open-end  diversified
management  investment company.  American Century - Twentieth Century Ultra Fund
(Ultra) and American  Century  Twentieth  Century Vista Fund (Vista) (the Funds)
are two of the seventeen series of funds issued by the  Corporation.  The Funds'
investment  objective is to seek capital growth by investing primarily in equity
securities.  On  September  3, 1996,  the Funds  implemented  a  multiple  class
structure whereby each Fund is authorized to issue three classes of shares:  the
Investor  Class,  the Advisor Class,  and the  Institutional  Class.  The shares
outstanding  prior to  September  3, 1996,  were  designated  as Investor  Class
shares.  The three  classes of shares  differ  principally  in their  respective
shareholder servicing and distribution expenses and arrangements.  All shares of
each Fund  represent  an equal pro rata  interest  in the assets of the class to
which such shares belong, and have identical voting,  dividend,  liquidation and
other  rights  and the same  terms and  conditions,  except  for class  specific
expenses  and  exclusive  rights to vote on matters  affecting  only  individual
classes.  Sale of the  Institutional  Class  commenced on November 14, 1996. The
following  significant  accounting  policies related to all classes of the Funds
are in accordance with accounting  policies generally accepted in the investment
company industry.

SECURITY  VALUATIONS  -- Portfolio  securities  traded  primarily on a principal
securities  exchange are valued at the last reported sales price, or the mean of
the  latest  bid and  asked  prices  where no last  sales  price  is  available.
Securities traded  over-the-counter are valued at the mean of the latest bid and
asked prices or, in the case of certain foreign securities, at the last reported
sales price,  depending on local  convention or regulation.  When valuations are
not readily  available,  securities  are valued at fair value as  determined  in
accordance with procedures adopted by the Board of Directors.

SECURITY  TRANSACTIONS  -- Security  transactions  are accounted for on the date
purchased  or  sold.  Net  realized  gains  and  losses  are  determined  on the
identified cost basis, which is also used for federal income tax purposes.

INVESTMENT  INCOME -- Dividend  income less foreign  taxes  withheld (if any) is
recorded as of the ex-dividend date.  Interest income is recorded on the accrual
basis and includes amortization of discounts and premiums.

FOREIGN  CURRENCY  TRANSACTIONS  -- The  accounting  records  of the  Funds  are
maintained in U.S. dollars.  All assets and liabilities  initially  expressed in
foreign currencies are converted into U.S. dollars at prevailing exchange rates.
Purchases and sales of investment securities,  dividend and interest income, and
certain  expenses  are  translated  at the rates of exchange  prevailing  on the
respective dates of such transactions.

Net  realized  foreign  currency  exchange  gains or losses  arise from sales of
foreign  currencies  and the  difference  between  asset and  liability  amounts
initially stated in foreign  currencies and the U.S. dollar value of the amounts
actually  received or paid. Net unrealized  foreign  currency  exchange gains or
losses  arise from  changes in the value of assets and  liabilities,  other than
portfolio securities, resulting from changes in the exchange rates.

Net realized and unrealized  foreign currency exchange gains or losses occurring
during the holding  period of portfolio  securities  are a component of realized
gain  (loss)  on  investments  and  unrealized  appreciation  (depreciation)  on
investments, respectively.

FORWARD FOREIGN CURRENCY EXCHANGE  CONTRACTS -- The Funds may enter into forward
foreign  currency  exchange  contracts  for the  purpose  of  settling  specific
purchases or sales of securities  denominated in a foreign  currency or to hedge
the Fund's  exposure  to  foreign  currency  exchange  rate  fluctuations.  When
required,  the Funds will segregate assets in an amount  sufficient to cover its
obligations  under the hedge  contracts.  The net U.S.  dollar  value of foreign
currency  underlying  all  contractual  commitments  held by the  Funds  and the
resulting  unrealized  appreciation or depreciation  are determined  daily using
prevailing exchange rates.  Forward contracts involve elements of risk in excess
of the amount  reflected in the Statement of Assets and  Liabilities.  The Funds
bear the risk of an  unfavorable  change in the foreign  currency  exchange rate
underlying  the  forward  contract.  Additionally,   losses  may  arise  if  the
counterparties do not perform under the contract terms.

REPURCHASE  AGREEMENTS -- The Funds may enter into  repurchase  agreements  with
institutions  the  Funds'  investment   manager,   American  Century  Investment
Management,  Inc. (ACIM),  has determined are creditworthy  pursuant to criteria
adopted by the Board of  Directors.  Each  repurchase  agreement  is recorded at
cost.  Each  Fund  requires  that  the  securities  purchased  in  a  repurchase
transaction  be  transferred  to the custodian in a manner  sufficient to enable
each  Fund to  obtain  those  securities  in the  event of a  default  under the
repurchase  agreement.  ACIM  monitors,  on a  daily  basis,  the  value  of the
securities  transferred to ensure that the value, including accrued interest, of
the  securities  under each  repurchase  agreement  is equal to or greater  than
amounts owed to each Fund under each repurchase agreement.

JOINT TRADING ACCOUNT -- Pursuant to an Exemptive Order issued by the Securities
and  Exchange  Commission,  each Fund,  along with other  registered  investment
companies having management agreements with ACIM and Benham


Semiannual Report                          Notes to Financial Statements      21



                          NOTES TO FINANCIAL STATEMENTS

APRIL 30, 1997 (UNAUDITED)

Management  Corporation,  may transfer  uninvested  cash  balances  into a joint
trading  account.  These  balances  are  invested  in  one  or  more  repurchase
agreements that are collateralized by U.S. Treasury or Agency obligations.

INCOME  TAX STATUS -- It is the policy of the Funds to  distribute  all  taxable
income and capital gains to shareholders and to otherwise qualify as a regulated
investment  company under provisions of the Internal Revenue Code.  Accordingly,
no provision has been made for federal income taxes.

DISTRIBUTIONS  TO SHAREHOLDERS --  Distributions to shareholders are recorded on
the ex-dividend date.  Distributions from net investment income and net realized
gains are declared and paid annually.

The character of distributions  made during the year from net investment  income
or net  realized  gains may differ  from  their  ultimate  characterization  for
federal  income tax purposes.  These  differences  are due to differences in the
recognition  of  income  and  expense  items  for  financial  statement  and tax
purposes.

SUPPLEMENTARY  INFORMATION -- Certain  officers and directors of the Corporation
are also officers and/or directors, and, as a group, controlling stockholders of
American Century  Companies,  Inc., the parent of the  Corporation's  investment
manager,  ACIM,  the  Corporation's  distributor,  American  Century  Investment
Services,  Inc., ACIS, and the  Corporation's  transfer agent,  American Century
Services Corporation.

USE OF ESTIMATES -- The  preparation of financial  statements in conformity with
generally accepted  accounting  principles requires management to make estimates
and assumptions  that affect the reported  amounts of assets and liabilities and
disclosure of  contingent  assets and  liabilities  at the date of the financial
statements,  and the reported  amounts of increases  and decreases in net assets
from operations  during the reporting  period.  Actual results could differ from
those estimates.

- --------------------------------------------------------------------------------
2. TRANSACTIONS WITH RELATED PARTIES

The Corporation has entered into a Management  Agreement with ACIM that provides
the Funds with  investment  advisory and  management  services in exchange for a
single,  unified management fee per class.  Additional fees apply to the Advisor
Class, as described in the respective propectus. The Agreement provides that all
expenses of the Funds, except brokerage commissions,  taxes, interest,  expenses
of those directors who are not considered "interested persons" as defined in the
Investment  Company  Act of 1940  (including  counsel  fees)  and  extraordinary
expenses, will be paid by ACIM. The fee is computed daily and paid monthly based
on each Fund's average daily closing net assets during the previous  month.  The
annual  management  fee is 1.00% for the Investor  Class,  0.75% for the Advisor
Class, and 0.80% for the Institutional Class.

The Board of Directors has adopted a shareholder  services and distribution plan
for the Advisor Class,  pursuant to Rule 12b-1 of the Investment  Company Act of
1940.  The Advisor  Class Master  Distribution  and  Shareholder  Services  Plan
provides that the Funds will pay ACIM an annual  distribution fee equal to 0.25%
and service fee equal to 0.25%.  The fees are  computed  daily and paid  monthly
based on the  Advisor  Class's  average  daily  closing  net  assets  during the
previous month.  The  distribution  fee provides  compensation  for distribution
expenses  incurred in connection with  distributing  shares of the Advisor Class
including,  but not limited to,  payments to  brokers,  dealers,  and  financial
institutions  that have entered into sales agreements with ACIS and/or ACIM. The
service fee provides  compensation for shareholder and  administrative  services
rendered by ACIM,  its  affiliates or independent  third party  providers.  Fees
incurred under the Master Distribution and Shareholder  Services Plan during the
six months ended April 30, 1997, were $37,498 for Ultra and $14,597 for Vista.


- --------------------------------------------------------------------------------
3. INVESTMENT TRANSACTIONS

The aggregate  cost of investment  securities  purchased  (excluding  short-term
investments)  for the six  months  ended  April  30,  1997,  for Ultra and Vista
totaled  $9,422,636,011,  and  $937,170,568,  respectively,  for common  stocks.
Proceeds from  investment  securities sold  (excluding  short-term  investments)
totaled $9,963,937,511 and $1,208,825,581, respectively, for common stocks.

As of April 30, 1997,  accumulated  net  unrealized  appreciation  for Ultra and
Vista was $4,211,447,185 and $211,628,438,  respectively, based on the aggregate
cost of  investments  for federal  income tax  purposes of  $14,633,537,685  and
$1,375,999,180,  respectively. Accumulated net unrealized appreciation consisted
of unrealized  appreciation of  $4,417,903,003  and  $330,896,602  for Ultra and
Vista,   respectively,   and  unrealized   depreciation  of   $206,455,818   and
$119,268,164, respectively.


22   Notes to Financial Statements                  American Century Investments
- --------------------------------------------------------------------------------


                          NOTES TO FINANCIAL STATEMENTS

APRIL 30, 1997 (UNAUDITED)
- --------------------------------------------------------------------------------
4. Capital Share Transactions

There are 750,000,000  shares of the Investor Class,  312,500,000  shares of the
Advisor Class, and 125,000,000 shares of the Institutional  Class authorized for
issuance  in  Ultra.  There  are  500,000,000  shares  of  the  Investor  Class,
210,000,000   shares  of  the  Advisor  Class,  and  80,000,000  shares  of  the
Institutional  Class  authorized for issuance in Vista. All shares are $0.01 par
value. Transactions in shares of the Funds were as follows:

<TABLE>
<CAPTION>
                                                                  ULTRA                              VISTA
                                                        Shares            Amount           Shares            Amount

- ------------------------------------------------------------------------------------------------------------------------
INVESTOR CLASS                                                                 (In Thousands)
- ------------------------------------------------------------------------------------------------------------------------
Six Months Ended April 30, 1997
<S>                                                    <C>            <C>                  <C>             <C>     
Sold ............................................      109,972        $3,251,197           35,756          $499,140

Issued in reinvestment of distributions..........       35,345         1,024,465           11,437           164,510

Redeemed.........................................    (115,658)       (3,415,367)         (55,625)         (780,590)
                                                  ------------      ------------     ------------      ------------

Net increase (decrease)..........................       29,659          $860,295          (8,432)        $(116,940)
                                                  ============      ============     ============      ============
- ------------------------------------------------------------------------------------------------------------------------
INVESTOR CLASS
- ------------------------------------------------------------------------------------------------------------------------
Year Ended October 31, 1996
Sold ............................................      194,099        $5,275,609           92,373        $1,404,556

Issued in reinvestment of distributions..........       26,782           669,557            7,805           109,657

Redeemed.........................................    (114,976)       (3,155,542)         (61,545)         (934,295)
                                                  ------------      ------------     ------------      ------------

Net increase.....................................      105,905        $2,789,624           38,633         $579,918
                                                  ============      ============     ============      ============
- ------------------------------------------------------------------------------------------------------------------------
ADVISOR CLASS
- ------------------------------------------------------------------------------------------------------------------------
Six Months Ended April 30, 1997
Sold ............................................          298            $8,547              224           $2,968

Issued in reinvestment of distributions..........           27               778               31              449

Redeemed.........................................        (153)           (4,292)            (171)           (2,158)
                                                  ------------      ------------     ------------      ------------

Net increase.....................................          172            $5,033              84             $1,259
                                                  ============      ============     ============      ============
- ------------------------------------------------------------------------------------------------------------------------
ADVISOR CLASS
- ------------------------------------------------------------------------------------------------------------------------
October 2, 1996(1) through October 31, 1996
Sold ............................................          443           $13,191              364           $6,124

Redeemed.........................................          (1)              (30)              (4)              (64)
                                                  ------------      ------------     ------------      ------------

Net increase.....................................          442           $13,161              360            $6,060
                                                  ============      ============     ============      ============
- ------------------------------------------------------------------------------------------------------------------------
INSTITUTIONAL CLASS
- ------------------------------------------------------------------------------------------------------------------------
November 14, 1996(2) through April 30, 1997
Sold ............................................          328           $10,075            1,138           $15,564

Issued in reinvestment of distributions..........           19               547               16               226

Redeemed.........................................        (343)           (9,722)               --                --
                                                  ------------      ------------     ------------      ------------

Net increase.....................................            4              $900           1,154            $15,790
                                                  ============      ============     ============      ============

(1) Commencement of sale of the Advisor Class.

(2) Commencement of sale of the Institutional Class.
</TABLE>


Semiannual Report                          Notes to Financial Statements      23



                          NOTES TO FINANCIAL STATEMENTS


APRIL 30, 1997 (UNAUDITED)

5. AFFILIATED COMPANY TRANSACTIONS

A summary  of  transactions  for each  issuer who is or was an  affiliate  at or
during the six months ended April 30, 1997, follows:
<TABLE>
                                       Share                                Realized
                                     Balance      Purchase        Sales        Gain                     Share       Market
Fund/Issuer                         10/31/96          Cost         Cost       (Loss)     Income        Balance      Value

- ---------------------------------------------------------------------------------------------------------------------------
ULTRA                                                                    ($ in Thousands)
- ---------------------------------------------------------------------------------------------------------------------------
<S>                               <C>             <C>           <C>           <C>        <C>       <C>              <C>     
Altera Corp.                              --      $220,321      $25,521       $1,902         --   4,745,000(1)     $235,174

Ascend Communications, Inc.       11,288,000       127,783      340,678      316,191         --             --           --

BMC Software, Inc.                 2,675,000        97,614       49,774        8,851         --   4,522,400(1)      195,311

C-Cube Microsystems Inc.           2,750,000       102,346      250,884      (54,799)        --             --           --

Cascade Communications Corp.       7,450,000        29,475      107,335      174,582         --             --           --

Citrix Systems, Inc.               1,900,000        51,851       73,263      (31,276)        --             --           --

DSP Communications, Inc.                  --        57,346       57,346      (36,516)        --             --           --

Evergreen Media Corporation        2,172,500            --       13,976        3,219         --      1,700,000       54,931

FORE Systems, Inc.                 4,900,000        31,821      142,037       53,568         --             --           --

Iomega Corporation                 7,300,000       115,315      181,589       (7,643)        --             --           --

LSI Logic Corp.                           --       235,172           --           --         --      7,000,000      267,750

Novellus Systems, Inc.                    --       127,347      127,347      (44,860)        --             --           --

Peoplesoft, Inc.                   2,900,000        13,524       81,015      164,390         --             --           --

Seagate Technology, Inc.                  --       238,124      112,966      (22,482)        --      6,600,000(1)   302,775

Starbucks Corp.                    4,000,000        40,857       32,542       (3,172)        --      3,000,000       89,250

Storage Technology Corp.                  --       125,865       25,205       (8,066)        --      2,600,000       91,325

Sun Microsystems, Inc.            13,450,000            --      262,213       87,605         --     14,537,800(1)   418,870

Teva Pharmaceutical
   Industries Ltd. ADR                    --       156,245           --           --       $177      2,850,000      143,925
U.S. Robotics Corp.                6,600,000        32,221      211,357      223,056         --             --           --

Western Digital Corp.                     --       241,875           --           --         --      3,500,000      215,688
                                                ----------   ----------   ---------- ----------                  ----------

                                                $2,045,102   $2,095,048     $824,550       $177                  $2,014,999
                                                ==========   ==========   ========== ==========                  ==========

- ------------------------------------------------------------------------------------------------------------------------
VISTA
- ------------------------------------------------------------------------------------------------------------------------
Aspen Technology, Inc.               500,000       $5,666      $11,337       $1,032          --        565,000(1)   $17,338

Brightpoint, Inc.                         --       30,937           --           --          --      1,512,500(1)    33,086

Cognos Incorporated                2,250,000           --       10,834       11,550          --      1,420,000       36,032

Comverse Technology, Inc.          1,650,000       57,514       17,195        1,405          --      1,300,000       51,350

Dura Pharmaceuticals, Inc.         2,200,000       12,362        6,487        1,746          --      2,000,000       58,125

Employee Solutions, Inc.           2,600,000       20,809       42,840       (9,102)         --             --           --
 
Hyperion Software Corp.                   --       12,658           --           --          --      1,400,000       22,575

IDEC Pharmaceuticals Corp.         1,000,000       32,350        9,872         (324)         --        540,000        9,652

Medicis Pharmaceutical Corp.         450,000        5,015       19,088       13,821          --        945,000(1)    23,212

Oregon Metallurgical Corp.           754,600       15,488       23,125       (5,850)         --             --           --

P-COM, Inc.                          850,000        7,304           --           --          --      1,050,000       29,794

PairGain Technologies, Inc.        2,200,000       30,246       40,583       45,853          --      1,820,000(1)    47,206

Rational Software Corp.            2,200,000           --       22,506       (8,697)         --      1,300,000       17,956

Sanmina Corp.                             --        9,663       20,744         (381)         --        850,000       42,553

Whole Foods Market, Inc.             950,000       33,246       37,055      (10,979)         --             --           --

                                                ----------   ----------   ---------- ----------                  ----------
                                                 $273,258     $261,666      $40,074          --                    $388,879
                                                ==========   ==========   ========== ==========                  ==========

(1)  Includes  adjustments  for shares  received  from stock split  and/or stock
     spinoff during the period.
</TABLE>

24   Notes to Financial Statements                  American Century Investments



                          NOTES TO FINANCIAL STATEMENTS


APRIL 30, 1997 (UNAUDITED)
- --------------------------------------------------------------------------------
6. CORPORATE EVENTS


The following name changes became effective January 1, 1997:

<TABLE>
                             NEW NAMES                                                  FORMER NAMES
- ------------------------------------------------------------------------------------------------------------------------
<S>                        <C>                                                          <C> 
Funds' Issuer:             American Century Mutual Funds, Inc.                          Twentieth Century Investors, Inc.

Funds:                     American Century - Twentieth Century Ultra Fund              Ultra Investors
                           American Century - Twentieth Century Vista Fund              Vista Investors

Parent Company:            American Century Companies, Inc.                             Twentieth Century Companies, Inc.

Distributor:               American Century Investment Services, Inc.                   Twentieth Century Securities, Inc.

Transfer Agent:            American Century Services Corporation                        Twentieth Century Services, Inc.
</TABLE>


Semiannual Report                          Notes to Financial Statements      25


<TABLE>
<CAPTION>
                              FINANCIAL HIGHLIGHTS
                                      ULTRA


                                                     For a Share Outstanding Throughout the Years Ended October 31 (except as noted)


                                                                                      Investor Class
                                                                 ----------------------------------------------------------

                                                              1997(1)       1996      1995       1994       1993       1992

- ---------------------------------------------------------------------------------------------------------------------------
PER-SHARE DATA
- ---------------------------------------------------------------------------------------------------------------------------
<S>                                                            <C>        <C>       <C>        <C>        <C>        <C>   
Net Asset Value, Beginning of Period........................   $29.52     $28.03    $21.16     $21.61     $15.46     $15.53
                                                              -------    -------   -------    -------    -------    -------

Income From Investment Operations
     Net Investment Income (Loss)...........................  0.02(2)  (0.05)(2) (0.07)(2)     (0.03)     (0.09)     (0.05)

     Net Realized and Unrealized Gain (Loss)
     on Investment Transactions.............................     1.26       2.84      7.58     (0.42)       6.24     (0.02)
                                                              -------    -------   -------    -------    -------    -------

     Total From Investment Operations.......................     1.28       2.79      7.51     (0.45)       6.15     (0.07)
                                                              -------    -------   -------    -------    -------    -------

Distributions
     From Net Realized Gains
     on Investment Transactions.............................   (1.69)     (1.19)    (0.64)         --         --         --

     Distributions in Excess
     of Net Realized Gains..................................       --     (0.11)        --         --         --         --
                                                              -------    -------   -------    -------    -------    -------

     Total Distributions....................................   (1.69)     (1.30)    (0.64)         --         --         --
                                                              -------    -------   -------    -------    -------    -------

Net Asset Value, End of Period..............................   $29.11     $29.52    $28.03     $21.16     $21.61     $15.46
                                                              -------    -------   -------    -------    -------    -------
                                                              -------    -------   -------    -------    -------    -------

     Total Return(3)........................................    4.35%     10.79%    36.89%    (2.08)%     39.78%    (0.45)%


- ---------------------------------------------------------------------------------------------------------------------------
RATIOS/SUPPLEMENTAL DATA
- ---------------------------------------------------------------------------------------------------------------------------
     Ratio of Operating Expenses
     to Average Net Assets.................................. 1.00%(4)      1.00%     1.00%      1.00%      1.00%      1.00%

     Ratio of Net Investment Income
     to Average Net Assets.................................. 0.11%(4)    (0.20)%   (0.30)%    (0.10)%    (0.60)%    (0.40)%

     Portfolio Turnover Rate................................      51%        87%       87%        78%        53%        59%

     Average Commission Paid per
     Investment Security Traded.............................  $0.0327    $0.0350   $0.0330      --(5)      --(5)      --(5)

     Net Assets, End of Period (in millions)................  $18,874    $18,266   $14,376    $10,344     $8,037     $4,275


(1)  Six months ended April 30, 1997 (unaudited).

(2)  Computed using average shares outstanding throughout the period.

(3)  Total  return   assumes   reinvestment   of  dividends  and  capital  gains
     distributions, if any. Total returns for periods less than one year are not
     annualized.

(4)  Annualized.

(5)  Disclosure of average  commission  paid per investment  security traded was
     not required prior to the year ended October 31, 1995.
</TABLE>

See Notes to Financial Statements


26   Financial Highlights                           American Century Investments


<TABLE>
<CAPTION>
                              FINANCIAL HIGHLIGHTS
                                      ULTRA
                                                          For a Share Outstanding Throughout the Periods Ended as Indicated

                                                                                                              ADVISOR 
                                                                                                               CLASS

                                                                                                       1997(1)      1996(2)

- ---------------------------------------------------------------------------------------------------------------------------
PER-SHARE DATA
- ---------------------------------------------------------------------------------------------------------------------------
<S>                                                                                                     <C>          <C>   
Net Asset Value, Beginning of Period.................................................................   $29.52       $29.55
                                                                                                       -------      -------

Income From Investment Operations
     Net Investment Loss(3)..........................................................................   (0.02)       (0.02)

     Net Realized and Unrealized Gain (Loss) on Investment Transactions..............................     1.26       (0.01)
                                                                                                       -------      -------

     Total From Investment Operations................................................................     1.24       (0.03)
                                                                                                       -------      -------

Distributions
     From Net Realized Gains on Investment Transactions..............................................   (1.69)           --
                                                                                                       -------      -------

Net Asset Value, End of Period.......................................................................   $29.07       $29.52
                                                                                                       -------      -------
                                                                                                       -------      -------

     Total Return(4).................................................................................    4.21%      (0.10)%


- ------------------------------------------------------------------------------------------------------------------------
RATIOS/SUPPLEMENTAL DATA
- ------------------------------------------------------------------------------------------------------------------------
     Ratio of Operating Expenses to Average Net Assets............................................... 1.25%(5)     1.25%(5)

     Ratio of Net Investment  Income to Average Net Assets...........................................(0.14)%(5)  (0.80)%(5)

     Portfolio Turnover Rate.........................................................................      51%          87%

     Average Commission Paid per Investment Security Traded..........................................  $0.0327      $0.0350

     Net Assets, End of Period (in millions).........................................................      $18          $13



(1)  Six months ended April 30, 1997 (unaudited).

(2)  October 2, 1996 (commencement of sale of Advisor Class) through October 31, 1996.

(3)  Computed using average shares outstanding throughout the period.

(4)  Total  return   assumes   reinvestment   of  dividends  and  capital  gains
     distributions, if any. Total returns for periods less than one year are not
     annualized.

(5)  Annualized.
</TABLE>

See Notes to Financial Statements


Semiannual Report                                   Financial Highlights      27

<TABLE>
<CAPTION>
                              FINANCIAL HIGHLIGHTS
                                      ULTRA


                                                           For a Share Outstanding Throughout the Period Ended as Indicated

                                                                                                              INSTITUTIONAL
                                                                                                                  CLASS 
                                                                                                         ------------------

                                                                                                                    1997(1)
- ---------------------------------------------------------------------------------------------------------------------------
PER-SHARE DATA
- ---------------------------------------------------------------------------------------------------------------------------
<S>                                                                                                                  <C>   
Net Asset Value, Beginning of Period............................................................................     $30.78
                                                                                                                    -------

Income From Investment Operations
     Net Investment Income(2)...................................................................................       0.03

     Net Realized and Unrealized Gain on Investment Transactions................................................       0.02
                                                                                                                    -------
     Total From Investment Operations...........................................................................       0.05
                                                                                                                    -------

Distributions
     From Net Realized Gains on Investment Transactions.........................................................     (1.69)
                                                                                                                    -------

Net Asset Value, End of Period..................................................................................     $29.14
                                                                                                                    -------
                                                                                                                    -------
     Total Return(3)............................................................................................      0.18%

- ---------------------------------------------------------------------------------------------------------------------------
RATIOS/SUPPLEMENTAL DATA
- ---------------------------------------------------------------------------------------------------------------------------
     Ratio of Operating Expenses to Average Net Assets..........................................................   0.80%(4)

     Ratio of Net Investment Income to Average Net Assets.......................................................   0.21%(4)

     Portfolio Turnover Rate....................................................................................        51%

     Average Commission Paid per Investment Security Traded.....................................................    $0.0327

     Net Assets, End of Period (in thousands)...................................................................       $103



(1)  November 14, 1996 (commencement of sale of Institutional Class) through April 30, 1997 (unaudited).

(2)  Computed using average shares outstanding throughout the period.

(3)  Total  return   assumes   reinvestment   of  dividends  and  capital  gains
     distributions, if any. Total returns for periods less than one year are not
     annualized.

(4)  Annualized.
</TABLE>


See Notes to Financial Statements


28   Financial Highlights                           American Century Investments


<TABLE>
<CAPTION>
                              FINANCIAL HIGHLIGHTS
                                      VISTA


                                                     For a Share Outstanding Throughout the Years Ended October 31 (except as noted)


                                                                                       INVESTOR CLASS
                                                      ---------------------------------------------------------------------

                                                              1997(1)       1996       1995      1994        1993      1992
- ---------------------------------------------------------------------------------------------------------------------------
PER-SHARE DATA
- ---------------------------------------------------------------------------------------------------------------------------
<S>                                                            <C>        <C>        <C>       <C>         <C>       <C>   
Net Asset Value, Beginning of Period........................   $15.68     $15.73     $10.94    $12.24      $11.01    $10.53
                                                              -------    -------    -------   -------     -------   -------
Income From Investment Operations
     Net Investment Loss....................................(0.06)(2)  (0.11)(2)  (0.08)(2)    (0.08)      (0.07)    (0.04)

     Net Realized and Unrealized Gain (Loss)
     on Investment Transactions.............................   (2.97)       1.09       4.90      0.45        1.95      0.52
                                                              -------    -------    -------   -------     -------   -------

     Total From Investment Operations.......................   (3.03)       0.98       4.82      0.37        1.88      0.48
                                                              -------    -------    -------   -------     -------   -------

Distributions
     From Net Realized Gains
     on Investment Transactions.............................   (1.18)     (1.02)     (0.03)    (1.66)      (0.64)        --

     Distributions in Excess of Net Realized Gains..........       --     (0.01)         --    (0.01)      (0.01)        --
                                                              -------    -------    -------   -------     -------   -------

     Total Distributions....................................   (1.18)     (1.03)     (0.03)    (1.67)      (0.65)        --
                                                              -------    -------    -------   -------     -------   -------

Net Asset Value, End of Period..............................   $11.47     $15.68     $15.73    $10.94      $12.24    $11.01
                                                              -------    -------    -------   -------     -------   -------
                                                              -------    -------    -------   -------     -------   -------

     Total Return(3)........................................ (20.79)%      6.96%     44.20%     4.16%      17.71%     4.55%

- ---------------------------------------------------------------------------------------------------------------------------
RATIOS/SUPPLEMENTAL DATA
- ---------------------------------------------------------------------------------------------------------------------------
     Ratio of Operating Expenses
     to Average Net Assets.................................. 1.00%(4)      0.99%      0.98%     1.00%       1.00%     1.00%

     Ratio of Net Investment Income
     to Average Net Assets..................................(0.75)%(4)   (0.70)%    (0.60)%   (0.80)%     (0.60)%   (0.40)%

     Portfolio Turnover Rate................................      49%        91%        89%      111%        133%       87%

     Average Commission Paid per
     Investment Security Traded.............................  $0.0264    $0.0280    $0.0330     --(5)       --(5)     --(5)

     Net Assets, End of Period (in millions)................   $1,569     $2,276     $1,676      $792        $847      $830



(1)  Six months ended April 30, 1997 (unaudited).

(2)  Computed using average shares outstanding throughout the period.

(3)  Total  return   assumes   reinvestment   of  dividends  and  capital  gains
     distributions, if any. Total returns for periods less than one year are not
     annualized.

(4)  Annualized.

(5)  Disclosure of average  commission  paid per investment  security traded was
     not required prior to the year ended October 31, 1995.
</TABLE>

See Notes to Financial Statements


Semiannual Report                                   Financial Highlights      29


<TABLE>
<CAPTION>
                              FINANCIAL HIGHLIGHTS
                                      VISTA

                                                          For a Share Outstanding Throughout the Periods Ended as Indicated

                                                                                                         Advisor Class
                                                                                                 --------------------------

                                                                                                       1997(1)      1996(2)

- ---------------------------------------------------------------------------------------------------------------------------
PER-SHARE DATA
- ---------------------------------------------------------------------------------------------------------------------------
<S>                                                                                                     <C>          <C>   
Net Asset Value, Beginning of Period.................................................................   $15.67       $16.87
                                                                                                       -------      -------

Income From Investment Operations
     Net Investment Loss(3)..........................................................................   (0.06)       (0.02)

     Net Realized and Unrealized Loss on Investment Transactions.....................................   (2.97)       (1.18)
                                                                                                       -------      -------

     Total From Investment Operations................................................................   (3.03)       (1.20)
                                                                                                       -------      -------

Distributions
     From Net Realized Gains on Investment Transactions..............................................   (1.18)           --
                                                                                                       -------      -------

Net Asset Value, End of Period.......................................................................   $11.46       $15.67
                                                                                                       -------      -------
                                                                                                       -------      -------

     Total Return(4)................................................................................. (20.89)%      (7.11)%


- ------------------------------------------------------------------------------------------------------------------------
RATIOS/SUPPLEMENTAL DATA
- ------------------------------------------------------------------------------------------------------------------------
     Ratio of Operating Expenses to Average Net Assets............................................... 1.25%(5)     1.25%(5)

     Ratio of Net Investment Income to Average Net Assets............................................(1.00)%(5)  (1.20)%(5)

     Portfolio Turnover Rate.........................................................................      49%          91%

     Average Commission Paid per Investment Security Traded..........................................  $0.0264      $0.0280

     Net Assets, End of Period (in millions).........................................................       $5           $6



(1)  Six months ended April 30, 1997 (unaudited).

(2)  October 2, 1996 (commencement of sale of Advisor Class) through October 31, 1996.

(3)  Computed using average shares outstanding throughout the period.

(4)  Total  return   assumes   reinvestment   of  dividends  and  capital  gains
     distributions, if any. Total returns for periods less than one year are not
     annualized.

(5)  Annualized.
</TABLE>


See Notes to Financial Statements


30   Financial Highlights                           American Century Investments


<TABLE>
<CAPTION>
                              FINANCIAL HIGHLIGHTS
                                      VISTA

                                                           For a Share Outstanding Throughout the Period Ended as Indicated

                                                                                                             INSTITUTIONAL
                                                                                                                 CLASS
                                                                                                         ------------------
                                                                                                                    1997(1)
- ---------------------------------------------------------------------------------------------------------------------------
PER-SHARE DATA
- ---------------------------------------------------------------------------------------------------------------------------
<S>                                                                                                                  <C>   
Net Asset Value, Beginning of Period.............................................................................    $15.73
                                                                                                                    -------

Income From Investment Operations
     Net Investment Income(2)....................................................................................    (0.03)

     Net Realized and Unrealized Loss on Investment Transactions.................................................    (3.04)
                                                                                                                    -------

     Total From Investment Operations............................................................................    (3.07)
                                                                                                                    -------

Distributions
     From Net Realized Gains on Investment Transactions..........................................................    (1.18)
                                                                                                                    -------

Net Asset Value, End of Period...................................................................................    $11.48
                                                                                                                    -------
                                                                                                                    -------

     Total Return(3).............................................................................................  (21.02)%


- ---------------------------------------------------------------------------------------------------------------------------
RATIOS/SUPPLEMENTAL DATA
- ---------------------------------------------------------------------------------------------------------------------------
     Ratio of Operating Expenses to Average Net Assets...........................................................  0.80%(4)

     Ratio of Net Investment Income to Average Net Assets........................................................(0.50)%(4)

     Portfolio Turnover Rate.....................................................................................       49%

     Average Commission Paid per Investment Security Traded......................................................   $0.0264

     Net Assets, End of Period (in millions).....................................................................       $13



(1)  November 14, 1996 (commencement of sale of Institutional Class) through April 30, 1997 (unaudited).

(2)  Computed using average shares outstanding throughout the period.

(3)  Total  return   assumes   reinvestment   of  dividends  and  capital  gains
     distributions, if any. Total returns for periods less than one year are not
     annualized.

(4)  Annualized.
</TABLE>


See Notes to Financial Statements


Semiannual Report                                   Financial Highlights      31



                       SHARE CLASS AND RETIREMENT ACCOUNT
                                   INFORMATION


SHARE CLASSES

Until  September  3,  1996,  Ultra and Vista  issued  one class of fund  shares,
reflecting  the fact that most  investors  bought  their  shares  directly  from
American Century.  All investors paid the same annual unified management fee and
did not pay any  commissions  or other fees to  purchase  shares  from  American
Century.

But increasing numbers of investors are purchasing fund shares through financial
intermediaries who are ordinarily  compensated for the additional  services they
provide.  In September  1996,  American  Century began to offer three classes of
shares  for many of its  funds,  including  Ultra  and  Vista.  One class is for
investors who still buy directly from American Century, one is for investors who
buy through financial  intermediaries,  and the third is for large institutional
customers.

The original class of Ultra and Vista shares is called the INVESTOR  CLASS.  All
shares issued and outstanding  before September 3, 1996, have been designated as
Investor  Class  shares.  Investor  Class  shares  may also be  purchased  after
September 3, 1996.  Investor Class  shareholders  do not pay any  commissions or
other fees for purchase of fund shares directly from American Century. Investors
who buy Investor Class shares through a broker-dealer may be required to pay the
broker-dealer a transaction fee. THE PRICE AND PERFORMANCE OF THE INVESTOR CLASS
SHARES ARE LISTED IN NEWSPAPERS. NO OTHER CLASS IS CURRENTLY LISTED.

In  addition,   there  is  an  ADVISOR  CLASS,  which  is  sold  through  banks,
broker-dealers, insurance companies and financial advisors. Advisor Class shares
are subject to a 0.50% Rule 12b-1 service and distribution fee. Half of that fee
is available to pay for recordkeeping and administrative  services,  and half is
available  to  pay  for   distribution   services   provided  by  the  financial
intermediary  through  which the Advisor Class shares are  purchased.  The total
expense ratio of the Advisor Class shares is 0.25% higher than the total expense
ratio of the Investor Class shares.

There  is also  an  INSTITUTIONAL  CLASS,  which  is  available  to  endowments,
foundations,  defined benefit pension plans or financial  intermediaries serving
these  investors.  This class  recognizes the  relatively  lower cost of serving
institutional customers and others who invest at least $5 million in an American
Century fund or at least $10 million in multiple  funds.  In  recognition of the
larger  investments and account  balances and  comparatively  lower  transaction
costs, the total expense ratio of the  Institutional  Class shares is 0.20% less
than the total expense ratio of the Investor Class shares. All classes of shares
represent a pro rata  interest in the funds and  generally  have the same rights
and preferences.

RETIREMENT ACCOUNT INFORMATION

As required by law, any distributions you receive from an IRA and certain 403(b)
distributions  [not  eligible for  rollover to an IRA or to another  403(b)] are
subject to federal income tax withholding at the rate of 10% of the total amount
withdrawn,  unless you elect not to have withholding apply. If you don't want us
to withhold  on this  amount,  you may send us a written  notice not to have the
federal  income tax withheld.  Your written  notice is valid for six months from
the date of  receipt  at  American  Century.  Even if you plan to roll  over the
amount you withdraw to another tax-deferred  account, the withholding rate still
applies to the withdrawn  amount unless we have received a written notice not to
withhold federal income tax within six months prior to the withdrawal.

When  you plan to  withdraw,  you may  make  your  election  by  completing  our
Exchange/Redemption  form or an IRS Form W-4P. Call American  Century for either
form.  Your  written  election  is valid  for only six  months  from the date of
receipt at American Century. You may revoke your election at any time by sending
a written notice to us.

Remember,  even if you elect not to have income tax withheld, you are liable for
paying income tax on the taxable portion of your withdrawal. If you elect not to
have income tax withheld or you don't have enough income tax  withheld,  you may
be responsible  for payment of estimated tax. You may incur  penalties under the
estimated  tax rules if your  withholding  and  estimated  tax  payments are not
sufficient.


32 Share Class and Retirement Account Information   American Century Investments



                                      NOTES


Semiannual Report                                                    Notes    33



                                      NOTES


34   Notes                                          American Century Investments



                                      NOTES


Semiannual Report                                                    Notes    35



                             BACKGROUND INFORMATION


INVESTMENT PHILOSOPHY AND POLICIES

The  Twentieth  Century Group offers nine equity funds that invest in the stocks
of growing  companies,  both  domestically and  internationally.  The philosophy
behind these growth funds  focuses on three  important  principles.  First,  the
funds seek to own  successful  companies,  which we define as those with growing
earnings  and  revenues.  Second,  we attempt to keep the funds fully  invested,
regardless of short-term market activity. Experience has shown that market gains
can occur in  unpredictable  spurts and that  missing  those  opportunities  can
significantly  limit the  potential  for gain.  Third,  the funds are managed by
teams, rather than by one "star." We believe this allows us to make better, more
consistent management decisions.

In addition to these principles, each fund has its own investment policies:

TWENTIETH  CENTURY ULTRA  generally  invests in the  securities of mid-sized and
larger companies that exhibit growth.  It will typically have significant  price
fluctuations.

TWENTIETH  CENTURY  VISTA  invests  mainly  in  the  securities  of  smaller  or
medium-sized firms that exhibit growth.  Although Vista has been one of American
Century's  more  volatile  funds over the short term,  it has also  offered high
potential for long-term growth.




FUND MANAGEMENT TEAM LEADERS
- ---------------------------------------------
Ultra:

Portfolio Manager Jim Stowers III

Portfolio Manager Bruce Wimberly



Vista:

Portfolio Manager Glenn Fogle

Portfolio Manager John Seitzer
- ---------------------------------------------



COMPARATIVE INDICES

The  following  indices  are used in the  report  to  serve as fund  performance
comparisons. They are not investment products available for purchase.

The S&P 500 is a capitalization-weighted  index of the stocks of the 500 largest
publicly traded U.S. companies.  Created by Standard & Poor's Corporation, it is
considered to be a broad measure of U.S. stock market performance.

The S&P MIDCAP 400 is a  capitalization-weighted  index of the stocks of the 400
largest  publicly traded U.S.  companies not included in the S&P 500. Created by
Standard & Poor's Corporation,  it is considered to represent the performance of
mid-cap stocks generally.

The RUSSELL 2000 INDEX was created by the Frank Russell Company. It measures the
performance  of the 2,000  smallest of the 3,000  largest  publicly-traded  U.S.
companies  based on total market  capitalization.  The Russell  2000  represents
approximately 10% of the total market capitalization of the top 3,000 companies.
The average market capitalization of the index is approximately $420 million.

The RUSSELL 2500 INDEX was created by the Frank Russell Company. It measures the
performance  of the 2,500  smallest of the 3,000  largest  publicly-traded  U.S.
companies  based on total market  capitalization.  The Russell  2500  represents
approximately 23% of the total market capitalization of the top 3,000 companies.
The average market  capitalization  of the index is approximately  $650 million.
The RUSSELL 2500 GROWTH INDEX  measures the  performance  of those  Russell 2500
companies with higher price-to-book ratios and higher forecasted growth values.

The NASDAQ  COMPOSITE  INDEX is a market  capitalization  price-only  index that
reflects  the   aggregate   performance   of  domestic   common   stocks  traded
"over-the-counter"  on the regular  Nasdaq  market,  as well as national  market
system-traded  foreign  common stocks and American  Depositary  Receipts.  It is
considered  to  represent  the   performance  of  smaller   capitalization   and
growth-oriented U.S. stocks.



36   Background Information                         American Century Investments



                                    GLOSSARY


RETURNS

o Total  Return  figures  show the overall  percentage  change in the value of a
hypothetical  investment  in  the  fund  and  assume  that  all  of  the  fund's
distributions are reinvested.

o Average Annual Returns  illustrate the annually  compounded returns that would
have produced the fund's cumulative total returns if the fund's  performance had
been  constant  over the  entire  period.  Average  annual  returns  smooth  out
variations  in a fund's  return;  they are not the same as  fiscal  year-by-year
results.  For fiscal year-by-year total returns,  please refer to the "Financial
Highlights" on pages 26-31.

PORTFOLIO STATISTICS

o Number of  Companies--  the number of different  companies held by a fund on a
given date.

o Price/Earnings (P/E) Ratio-- a stock value measurement  calculated by dividing
a company's stock price by its earnings per share,  with the result expressed as
a multiple  instead of as a  percentage.  (Earnings  per share is  calculated by
dividing the after-tax earnings of a corporation by its outstanding shares.)

o Portfolio  Turnover-- the percentage of a fund's investment  portfolio that is
replaced during a given time period, usually a year. Actively managed portfolios
tend to have higher  turnover than passively  managed  portfolios  such as index
funds.

o Expense Ratio-- the operating expenses of the fund,  expressed as a percentage
of average net assets. Share-holders pay an annual fee to the investment manager
for  investment  advisory  and  management  services.  The expenses and fees are
deducted from fund income, not from each shareholder account. (See Note 2 in the
Notes to Financial Statements.) 

TYPES OF STOCKS

o  Blue-Chip  Stocks--  stocks of the most  established  companies  in  American
industry.   They  are  generally  large,   fairly  stable  companies  that  have
demonstrated  consistent  earnings and usually have long-term growth  potential.
Examples include General Electric and Coca-Cola.

o Cyclical Stocks--  generally  considered to be stocks whose price and earnings
fluctuations  tend to follow the ups and downs of the business  cycle.  Examples
include the stocks of  automobile  manufacturers,  steel  producers  and textile
operators.

o Growth  Stocks--  stocks  of  companies  that have  experienced  above-average
earnings  growth and appear likely to continue  such growth.  These stocks often
sell at  high  P/E  ratios.  Examples  can  include  the  stocks  of  high-tech,
healthcare and consumer staple companies.

o Large-Capitalization  ("Large-Cap") Stocks-- generally considered to be stocks
of  companies  with a market  capitalization  (the  total  value of a  company's
outstanding  stock) of more than $5  billion.  These tend to be the stocks  that
make up the Dow Jones Industrial Average and the S&P 500.

o  Medium-Capitalization  ("Mid-Cap") Stocks-- generally considered to be stocks
of  companies  with a market  capitalization  (the  total  value of a  company's
outstanding  stock) of between $1 billion and $5  billion.  These tend to be the
stocks that make up the S&P 400.

o Small-Capitalization  ("Small-Cap") Stocks-- generally considered to be stocks
of  companies  with a market  capitalization  (the  total  value of a  company's
outstanding  stock) of less than $1  billion.  These tend to be the stocks  that
make up the Russell 2000 Index.

o Value Stocks--  generally  considered to be stocks that are purchased  because
they are relatively inexpensive. These stocks are typically characterized by low
P/E ratios.

STATISTICAL TERMINOLOGY

o  Price/Book  Ratio--  a stock  value  measurement  calculated  by  dividing  a
company's stock price by its book value per share,  with the result expressed as
a multiple  instead of as a  percentage.  (Book value per share is calculated by
subtracting a company's liabilities from its assets, then dividing that value by
the number of outstanding shares.)



Semiannual Report                                                    Glossary 37



[american century logo]
American
Century(sm)


P.O. Box 419200
Kansas City, Missouri
64141-6200

Investor Services:
1-800-345-2021 or 816-531-5575

Automated Information Line:
1-800-345-8765

Telecommunications Device for the Deaf:
1-800-634-4113 or 816-444-3485

Fax: 816-340-7962

Internet: www.americancentury.com



AMERICAN CENTURY MUTUAL FUNDS, INC.

Investment Manager
AMERICAN CENTURY INVESTMENT MANAGEMENT, INC.
Kansas City, Missouri

This report and the financial  statements contained herein are submitted for the
general  information  of our  shareholders.  The  report is not  authorized  for
distribution  to  prospective  investors  unless  preceded or  accompanied by an
effective prospectus.

American Century Investment Services, Inc.



9706           [recycled logo]
SH-BKT-8626       Recycled
<PAGE>
                               SEMIANNUAL REPORT

                            [american century logo]
                                    American
                                  Century(sm)

                                 APRIL 30, 1997

                                   TWENTIETH
                                    CENTURY
                                     GROUP

                                    Giftrust

[front cover]


                               TABLE OF CONTENTS

Report Highlights...........................................................1
Our Message to You..........................................................2
Period Overview.............................................................3
Performance & Portfolio Information.........................................4
Management Q & A............................................................5
Schedule of Investments.....................................................8
   Statement of Assets and Liabilities.....................................10
Statement of Operations....................................................11
Statements of Changes in Net Assets........................................12
Notes to Financial Statements..............................................13
Financial Highlights.......................................................15
Background Information
   Investment Philosophy and Policies......................................16
   Comparative Indices.....................................................16
   Fund Management Team Leaders............................................16
Glossary...................................................................17

American Century  Investments offers you nearly 70 fund choices covering stocks,
bonds, money markets,  specialty investments and blended portfolios. To help you
find the funds that may meet your needs, we have divided  American Century funds
into three groups based on investment style and objectives.  These groups, which
appear below, are designed to help simplify your fund decisions.

                  American Century Investments--Family of Funds

     Benham Group            American Century Group      Twentieth Century Group

  MONEY MARKET FUNDS           ASSET ALLOCATION &
 GOVERNMENT BOND FUNDS           BALANCED FUNDS                GROWTH FUNDS
DIVERSIFIED BOND FUNDS      CONSERVATIVE EQUITY FUNDS      INTERNATIONAL FUNDS
 MUNICIPAL BOND FUNDS            SPECIALTY FUNDS
                                                                 Giftrust

We welcome your comments or questions about this report.  
See the back cover for ways to contact us by mail, phone or e-mail.

Twentieth  Century and the Benham Group are registered marks of American Century
Services Corporation and Benham Management Corporation,  respectively.  American
Century is a service mark of American Century Services Corporation.


                                                    American Century Investments


                               REPORT HIGHLIGHTS

PERIOD OVERVIEW

o The U.S. stock market produced widely divergent  returns over the period.  The
S&P  500's  14.74%  six-month  total  return  continued  a  three-year  trend of
unusually strong  performance by large-cap stocks.  By contrast,  the S&P MidCap
400 posted a 6.88% return, and the small-cap Russell 2000 returned just 1.61%.

o Factors that were in the S&P 500's favor included:  equity  investors  seeking
stability and liquidity;  strong  economic  growth with low  inflation;  and the
success of index funds.

o The  fast-growing  companies  targeted by  Giftrust  didn't  benefit  from the
factors  that drove  investors  to the S&P 500.  This  happened  despite  strong
earnings growth on the part of most companies owned by the fund.

GIFTRUST

o  Giftrust  suffered  one of the  steepest  short-term  declines  in the fund's
13-year  history.  The drop  resulted  from the decline of  small-capitalization
(small-cap)  growth  stocks,  compounded by the fund's focus on the most rapidly
growing companies within that group.

o The technology sell-off allowed the investment team to build positions in more
seasoned,  high  quality  names.  These are the  stocks the team  believes  will
rebound strongly when the market again favors fast-growing companies.

o Holdings increased in semiconductor  companies,  energy services companies and
biotechnology firms. Among semiconductor  companies,  the fund has invested in a
small group of elite  manufacturers of specialized,  high-speed  computer chips.
These  chips are in demand as  telecommunications  networks  expand  around  the
globe.

o The management team reduced computer  software  holdings because of increasing
competition and low barriers to entry in this industry.

o For the past two years the largest  stocks in the S&P 500 index have seemingly
offered  everything an investor  could desire:  strong  earnings  growth,  above
average  returns,  low  volatility  and superior  liquidity.  To some extent the
extraordinary  returns have also been  self-perpetuating,  as momentum-following
market participants have sold their underperforming  stocks (often small-cap) to
buy the  large-cap  leaders.  Giftrust's  management  team  believes a change in
market leadership will probably begin with a deteriorating outlook for earnings,
and that change may not be too far away.

                                    GIFTRUST

                         TOTAL RETURNS:   AS OF 4/30/97
                           6 Months          -24.36%(1)
                           1 Year               -27.08%

                         NET ASSETS:       $723 million
                           (AS of 4/30/97)

                         INCEPTION DATE:       11/25/83

                         TICKER SYMBOL:           TWGTX

                         (1) Not annualized.

Many of the investment  terms in this report are defined in the Glossary on page
17.


Semiannual Report                                         Report Highlights    1


                               OUR MESSAGE TO YOU

           [photo of James E. Stowers, Jr. and James E. Stowers III]

April 30,  1997,  marked the end of an  eventful  period for the company and the
Twentieth  Century   aggressive  growth  funds.  We  entered  1997  with  a  new
identity--American Century Investments. American Century encompasses the skills,
talent and resources  brought  together when Twentieth  Century Mutual Funds and
The Benham Group merged during 1995 and 1996.

Changing the company's name after being known as Twentieth  Century Mutual Funds
for  almost  40 years  was a  significant  step.  Although  our core  investment
disciplines  remain  unchanged,  the combination of Twentieth Century and Benham
allows us to bring you a full menu of nearly 70 funds.  Our offerings range from
conservative  money  market  funds  carrying  the Benham name to the nine equity
growth funds that still carry the Twentieth Century name and employ our hallmark
growth-oriented investment approach.

The six-month period ended April 30, 1997, was a challenge for aggressive growth
funds such as Giftrust. As investors sought size, stability and familiarity, the
S&P 500 and funds that mirror the index  outperformed  growth funds investing in
smaller companies and emerging industries. These factors had an especially large
impact on the short-term performance of Giftrust.

Given this environment, it is important to remember that investing in aggressive
growth funds involves  significant  short-term  volatility.  Over the long term,
however,  an  aggressive  growth  strategy  can provide the kind of  significant
capital  growth  that  builds  wealth.  Investors  need  patience to weather the
market's cycles and realize the strategy's potential benefits.

We have steadily refined the growth  discipline  pioneered at Twentieth  Century
over the past 25 years,  enabling our teams to identify and invest in businesses
that are among the  fastest  growing in the  world.  We are  confident  that our
approach will continue to reward patient investors who stay the course.

A large part of helping investors remain patient and confident in their funds is
regularly providing the best possible  information in a helpful format. Based on
investors'  feedback,  we have redesigned our shareholder reports to include new
features such as a one-page report summary, a glossary,  more charts and graphs,
and expanded  Management Q&A and background  information  sections.  This report
displays the new format.

We appreciate your confidence in American Century and look forward to continuing
to serve you.

Sincerely,
/s/James E. Stowers, Jr.                  /s/James E. Stowers III
James E. Stowers, Jr.                     James E. Stowers III
Chairman of the Board and Founder         President and Chief Executive Officer


2    Our Message to You                             American Century Investments


                                PERIOD OVERVIEW

[line graph - data below]

U.S. STOCK MARKET PERFORMANCE (Growth of $1.00)
For the six monthes ended April 30, 1997
- -------------------------------------------------------------------
DATE     S&P 500           S&P 400          RUSSELL 2000

10/31/96 $1.00             $1.00            $1.00
11/30/96 $1.07             $1.06            $1.04
12/31/96 $1.06             $1.06            $1.07
1/31/97  $1.12             $1.10            $1.09
2/28/97  $1.13             $1.09            $1.06
3/31/97  $1.08             $1.04            $1.01
4/30/97  $1.15             $1.07            $1.02

S&P 500..............14.74%
S&P MidCap 400 ...... 6.88%
Russell 2000..........1.61%
Source: Lipper Analytical Services, Inc.

WIDELY DIVERGENT RETURNS

The six-month period ended April 30, 1997, produced widely divergent returns for
U.S.  stock  investors.  In general,  the shares of large  companies  (large-cap
stocks), particularly relatively stable,  industry-leading firms in the S&P 500,
significantly outperformed the shares of faster-growing, smaller companies (mid-
and small-cap stocks).  Value stocks (shares of companies that are lower priced)
generally   outperformed   growth  stocks  (those  of  companies   demonstrating
above-average  earnings growth) as investors placed a higher premium on earnings
stability than on earnings growth.

STRONG RETURNS FOR THE S&P 500

The S&P 500 typically  represents the large-cap sector of the U.S. stock market.
Many investors also use the index as a proxy for the U.S. market as a whole. The
sustained  advance  of the S&P 500 was  one of the key  success  stories  of the
period. The index posted a 14.74% total return during the six months, continuing
a three-year trend of unusually  strong results.  Factors that supported the S&P
500's performance included:

o Investors  seeking  predictable  earnings  and  liquidity  because they feared
rising interest rates and an economic slowdown. The shares of large,  well-known
firms such as Johnson & Johnson and Microsoft rallied appreciably.

o  Favorable   economic   conditions  (robust  growth  and  low  inflation)  and
particularly strong earnings growth for large-cap companies.

o The popularity and success of S&P 500 index funds.  With more investor dollars
chasing  stocks in the S&P 500, the prices of those shares rose much faster than
the prices of mid- and small-cap stocks.

LOWER RETURNS FOR SMALLER-CAP STOCKS

Many  analysts  use the S&P  MidCap  400 Index  and the  Russell  2000  Index to
represent mid- and small-cap stocks, respectively.  As shown in the accompanying
graph, the S&P 500 significantly outperformed the smaller-cap indices.

While the S&P 500 and its component  companies were considered a relatively safe
haven  during the  period,  many  investors  viewed  mid- and  small-cap  growth
companies as too volatile and unpredictable.  Valuations for the stocks of these
companies  declined as the market priced mid- and  small-cap  growth stocks more
conservatively,  weighting  current  earnings more heavily than projected future
earnings.  Investors also became less willing to pay a premium for  fast-growing
technology and healthcare shares.

The resulting price declines were generally based more on market perception than
on changes in actual fundamental  indicators such as earnings and revenue.  Many
companies  experienced  lower share  prices  despite  continuing  to show strong
operating results. Defensive-minded analysts questioned whether the earnings and
revenue  projections  of mid- and  small-cap  companies  would be realized,  and
investors refused to pay the higher prices these shares have been awarded in the
past.


Semiannual Report                                           Period Overview    3


                      PERFORMANCE & PORTFOLIO INFORMATION


TOTAL RETURNS AS OF APRIL 30, 1997
                                                 AVERAGE ANNUAL RETURNS
                          6 MONTHS   1 YEAR    3 YEARS   5 YEARS  10 YEARS

   GIFTRUST.............. -24.36%   -27.08%    10.56%    17.16%    14.74%
   Russell 2000 Growth... -7.36%    -13.61%     9.39%     9.69%     7.26%

See pages 16 and 17 for more information about the Russell 2000 Growth Index and
returns.


PORTFOLIO AT A GLANCE
                                     4/30/97     10/31/96
Number of Companies                    73           70
Median Price/Earnings Ratio           27.9         47.8
Portfolio Turnover                   68%(1)       121%(2)
Expense Ratio                       1.00%(3)       0.98%

(1) Six months ended 4/30/97.
(2) Year ended 10/31/97.
(3) Annualized.

[line graph - data below]

GROWTH OF $10,000 OVER 10 YEARS
VALUE ON 4/30/97:
     "$39,536 "   GIFTRUST
     "$30,175 "   NASDAQ
     "$20,156 "   RUSSELL 2000 GROWTH

               GIFTRUST           NASDAQ      RUSSELL 2000 GROWTH
DATE          ACCT VALUE        ACCT VALUE       ACCT VALUE

4/30/87        $10,000           $10,000           $10,000
4/30/88         $8,756            $9,077            $8,734
4/30/89        $10,495           $10,233            $9,860
4/30/90        $11,881           $10,054            $9,924
4/30/91        $13,797           $11,601           $11,193
4/30/92        $17,907           $13,850           $12,695
4/30/93        $22,528           $15,831           $13,444
4/30/94        $29,251           $17,564           $15,398
4/30/95        $38,680           $20,200           $16,743
4/30/96        $54,215           $28,495           $23,332
4/30/97        $39,536           $30,175           $20,156

Past  performance  does not  guarantee  future  results.  Investment  return and
principal  value will fluctuate,  and redemption  value may be more or less than
original cost. The line representing  Giftrust's total return includes operating
expenses (such as transaction  costs and management  fees) that reduce  returns,
while the total return lines of the indices do not.


[bar chart - data below]

GIFTRUST'S ONE-YEAR RETURNS OVER 10 YEARS (Periods ended April 30)

                   GIFTRUST              RUSSELL 2000
DATE                 RETURN                    RETURN
4/30/88             -12.44%                   -12.66%
4/30/89              19.86%                    12.89%
4/30/90              13.21%                     0.64%
4/30/91              16.12%                    12.79%
4/30/92              29.79%                    13.42%
4/30/93              25.80%                     5.90%
4/30/94              29.84%                    14.54%
4/30/95              32.24%                     8.73%
4/30/96              40.16%                    39.35%
4/30/97             -27.08%                   -13.61%

This chart  illustrates  the fund's  returns over the past 10 years and compares
them with the Russell 2000 Growth's  returns.  Giftrust's  total returns include
operating expenses,  while the Russell 2000 Growth's returns do not. See page 16
for a  description  of the index.  Past  performance  is no  guarantee of future
results.


4    Performance & Portfolio Information            American Century Investments


                                MANAGEMENT Q & A

An  interview  with Glenn  Fogle and John  Seitzer,  portfolio  managers  on the
Giftrust management team.

HOW DID THE FUND PERFORM DURING THE SIX MONTHS ENDED APRIL 30?

Giftrust's  total return of -24.36%  represented one of the steepest  short-term
declines in the fund's 13-year history. The fund's negative performance resulted
from the generally unfavorable investment  environment for  small-capitalization
(small-cap)  growth stocks,  compounded by our focus on the most rapidly growing
companies  within  that  sector  of  the  market.  Our  concentration  on  these
businesses,  hardest hit by the market's turbulence, caused the fund to suffer a
greater decline than benchmark market indices.

When reflecting on this six-month  performance,  it's important to remember that
we manage Giftrust  aggressively for optimum long-term returns. As a result, the
fund historically has been very volatile,  sometimes  underperforming the market
dramatically  and  other  times  outperforming  it  significantly.  (To view how
Giftrust's  performance  has varied over  short-term  periods,  see the One-Year
Return graph on page 4.) Giftrust has rebounded sharply from similar performance
downswings. We cannot predict when this might occur, but we can assure investors
that we are accustomed to managing through periods of intense market  volatility
as well as the peaks and valleys in Giftrust's  performance  resulting  from our
investment style.

HOW LARGE WAS THE GENERAL DECLINE OF SMALL-CAP GROWTH STOCKS FOR THE PERIOD?

Many investment  analysts  consider the Russell 2000 Growth Index to be the most
appropriate  proxy for small-cap growth stock  performance.  This index posted a
- -7.36%  total  return  for the  period.  Stocks in this  sector  suffered  sharp
devaluations caused by investors fearing volatility and questioning the validity
of earnings and revenue projections for small-cap technology companies.

WHY WAS THE FUND'S PERFORMANCE BENCHMARK CHANGED FROM THE NASDAQ COMPOSITE INDEX
TO THE RUSSELL 2000 GROWTH INDEX?

The benchmark should resemble the holdings in Giftrust's portfolio as closely as
possible.  The  problem  with the Nasdaq  index is that it  contains a number of
large-cap companies such as Microsoft and Intel that have market capitalizations
in excess of $100 billion and do not appear in Giftrust's portfolio.  The Nasdaq
index's  performance can be greatly skewed by these heavyweight  companies.  The
component  companies  in the  Russell  index  are  closer  in size to  those  in
Giftrust.  The average  market  capitalization  of companies in the Russell 2000
Growth Index is  approximately  $400 million.  This  corresponds with Giftrust's
median market capitalization of $436 million at the end of the period.

WHY DID GIFTRUST'S  PERFORMANCE DIFFER SO MARKEDLY FROM THAT OF THE RUSSELL 2000
GROWTH INDEX?

Unlike an index fund,  Giftrust makes no attempt to match any benchmark  returns
over short-term  periods.  In seeking superior long-term returns,  the fund owns
companies  that have much  higher  growth  rates than  those in the index.  As a
result,  the fund  usually  appears more  expensive  than the index on valuation
measures.  Over time, we expect the exceptional earnings growth potential of the
stocks  Giftrust  owns  to more  than  offset  the  premium  paid  to buy  these
companies. In the short run, however, the fund can be very votatile and markedly
underperform the index.

Our management of the fund has remained consistent with our long-held investment
discipline.  We bought and now own some great growth businesses.  Unfortunately,
as  sometimes  happens,  the prices of many of those stocks have fallen since we
acquired them in spite of strong earnings reports. We are prepared to retain the
shares of good businesses  that meet our investment  standards even if they fall
temporarily out of favor and their share prices lag for a while.  While the past
is no guarantee of the future,  our experience  tells us that over the long term
we'll be rewarded with higher share prices.


Semiannual Report                                          Management Q & A    5


CAN YOU GIVE INVESTORS ENCOURAGEMENT ABOUT THE FUND'S PERFORMANCE?

There are several  factors that  encourage us about the  prospects for Giftrust.
The number of new stock  offerings  (IPOs)  has  declined  dramatically  in 1997
compared  to the prior two years,  stemming  the flood of new  issues  that were
crowding the market.  The sell-off in small-cap  growth stocks has brought their
valuation relative to large-cap stocks down to historically low levels. Finally,
the companies  Giftrust owns continue to report dynamic growth in their revenues
and earnings.

In  terms  of its  investment  philosophy  and  objectives,  Giftrust  is  still
essentially  the same  fund it was two  years  ago when it was  generating  high
returns.  We've  stuck to our basic  investment  discipline,  even  though  it's
currently out of favor. We've remained focused on long-term  results.  The stock
market,  like the economy,  moves in cycles.  Periods like the recent one,  when
uncertainty  about the  strength of the economy  and the  direction  of interest
rates make stock investors more  conservative,  are normal.  Eventually,  market
sentiment  should shift again, and when it does we would expect the fast-growing
stocks owned in Giftrust to reward investors for their patience.

WHAT CHANGES DID YOU MAKE IN THE FUND'S INVESTMENT STRATEGY OR HOLDINGS BASED ON
THE MARKET ENVIRONMENT?

We still own a  significant  number of  technology  stocks  because  the  sector
continues to produce high and rising earnings growth rates. However,  within the
technology group we shifted our focus to somewhat  stronger  companies with more
secure  businesses.  Because the  sell-off  in  technology  shares hit  industry
leaders as well as less established  companies,  we were able to build positions
in several more seasoned,  high quality  names.  These are the stocks we believe
will rebound strongly when the market once again favors fast-growing companies.

An example of our shift  toward  industry  leaders is HBO & Company,  a software
provider to the healthcare  industry (not Home Box Office,  the cable television
network).  A dominant force in this specialized  field, HBO provides software to
help hospitals manage back-office  administrative functions, track clinical data
and manage patient information flow. The company has expanded to serve physician
groups,  home  healthcare  and  managed  care  organizations  seeking to improve
efficiency.

WHAT OTHER CHANGES DID YOU MAKE IN THE FUND'S TECHNOLOGY HOLDINGS?

Apart  from  software  companies  with a  unique  niche  such as HBO,  we made a
strategic  decision to reduce our  investment  in the software  group because of
increasing  competition  and low  barriers  to  entry.  On the  other  hand,  we
increased our holdings in a small group of elite  manufacturers  of specialized,
high-speed  computer  chips.  These  companies  make  semiconductors  out  of  a
substance called gallium arsenide, which


TOP TEN HOLDINGS                     % of fund investments
                                     As of        As of
                                     4/30/97     10/31/96
McAfee Associates, Inc.               3.2%         1.0%
PAREXEL International Corp.           3.1%         1.8%
HBO & Co.                             2.9%          --
CBT Group Plc ADR                     2.5%         4.8%
P-COM, Inc.                           2.5%         1.4%
Jabil Circuit, Inc.                   2.5%          --
Vitesse Semiconductor Corp.           2.3%          --
Agouron Pharmaceuticals, Inc.         2.0%          --
Herman Miller, Inc.                   2.0%          --
ANADIGICS, Inc.                       1.9%          --


TOP FIVE INDUSTRIES                  % of fund investments
                                     As of        As of
                                     4/30/97     10/31/96
Computer Software & Services          14.3%        23.3%
Electrical & Electronic
    Components                        8.6%         0.9%
Communications Equipment              6.9%         5.1%
Energy (Services)                     6.9%         0.5%
Biotechnology                         6.5%         4.4%


6    Management Q & A                               American Century Investments


                                MANAGEMENT Q & A

processes data at faster speeds than conventional silicon.  Demand for the chips
is exploding and there are only a few suppliers  capable of manufacturing  them.
Vitesse  Semiconductor  Corporation and ANADIGICS,  Inc., two companies the fund
owns,  provide  chips  to  telecommunications   companies  serving  the  rapidly
expanding global telecommunications market. Gallium arsenide chips are playing a
key role in the expansion of internet  access and in the  deployment of standard
phone service via wireless networks in emerging countries.

IN WHAT OTHER INDUSTRIES IS GIFTRUST INVESTING?

We bought  energy  services  companies  after oil and gas  prices  dropped  this
winter. As a result of fundamental  restructuring in this industry, we're seeing
accelerating  earnings  that we  believe  are  sustainable.  Here,  as in  other
industries,   technology  is  driving  increased   productivity.   For  example,
geologists now routinely analyze  three-dimensional seismic data to find oil and
natural gas below the ocean floor.  With this more accurate view of the size and
location of undersea  reserves,  energy  companies can drill profitable wells in
locations that were previously economically unfeasible.

Biotechnology   is   another   sector   where  we  see   attractive   investment
opportunities. Many of the leading companies have new products in late stages of
development  that should come to market within the next 12 months.  For example,
Agouron  Pharmaceuticals,  Inc., a company the fund owns,  received  Food & Drug
Administration approval in March to market a new drug for treating AIDS patients
called Viracept. When used in combination with other drugs it has relatively few
side effects and  significantly  reduces the amount of HIV in patients'  bodies.
Sales of Viracept are accelerating as more patients add it to their therapy.

WHAT DO YOU THINK  WILL CAUSE THE MARKET  FOR  SMALL-CAP  GROWTH  STOCKS TO TURN
AROUND?

The  outperformance  of large-cap stocks over the past year has coincided with a
period of better than average (and better than expected) earnings growth,  which
we think is attributable to the  surprisingly  robust economy.  For the past two
years the largest stocks in the S&P 500 index have seemingly offered  everything
an investor could desire:  strong earnings growth,  above average  returns,  low
volatility and superior liquidity.

We  think  that a  change  in  market  leadership  will  probably  begin  with a
deteriorating outlook for earnings, and that change may not be too far away. The
pace of economic growth in the first months of 1997 is not sustainable,  and the
Federal  Reserve seems intent on ensuring  that the economy  cools down.  Slower
growth,  higher  interest  rates and a strong  dollar  all put  pressure  on the
earnings growth rates of larger companies.  With the profit margins at large-cap
companies  already at  historically  high levels,  it seems  probable that their
earnings  growth  rates will decline  over the next few  quarters.  Some smaller
companies will suffer the same deterioration,  but those that can buck the trend
should attract growth-oriented  investors. The inexpensive relative valuation of
small-cap stocks should also contribute to their recovery.

The year-long divergence between small-cap and large-cap stocks is very unusual,
which  suggests the strong  possibility  of a small-cap  rebound.  Unfortunately
there is no telling precisely when this might happen or to what degree. We avoid
trying to time the  market  (and we  discourage  fund  investors  from doing so)
because  market trends can reverse  abruptly and without  warning.  Instead,  we
concentrate  on  keeping  the fund well  positioned  with  investments  in good,
growing businesses with the strongest  fundamental outlook we can find. We don't
have any control  over the timing of how the market  reacts,  but we can control
our investment strategy and goals.

EDITOR'S NOTE ON JUNE 6, 1997:
SINCE APRIL 30,  GIFTRUST'S SHARE VALUE HAS RISEN BY 19% COMPARED TO AN INCREASE
OF ONLY 7% IN THE S&P 500.  THE  CHANGE  IN  MARKET  SENTIMENT  REGARDING  SMALL
COMPANIES MAY HAVE BEGUN.


Semiannual Report                                          Management Q & A    7


                            SCHEDULE OF INVESTMENTS


APRIL 30, 1997 (UNAUDITED)

Shares                    ($ in Thousands)                      Value
- ------------------------------------------------------------------------

COMMON STOCKS

AEROSPACE & DEFENSE--3.4%
   500,000    DONCASTERS plc ADR(1)(2)                        $ 11,250
   630,000    Wyman-Gordon Co.(1)                               13,309
                                                              --------
                                                                24,559
                                                              --------

AGRICULTURE--0.7%
   437,600    Northland Cranberries, Inc.                        5,087
                                                              --------

BIOTECHNOLOGY--6.5%
   230,000    Agouron Pharmaceuticals, Inc.(1)                  14,734
   430,000    Centocor, Inc.(1)                                 12,121
   266,800    Incyte Pharmaceuticals, Inc.(1)                   11,539
   175,000    Protein Design Labs, Inc.(1)                       4,386
   246,900    Sangstat Medical Corp.(1)                          4,259
                                                              --------
                                                                47,039
                                                              --------

BUSINESS SERVICES & SUPPLIES--5.7%
   382,500    ABR Information Services, Inc.(1)                  7,746
   600,000    PMT Services, Inc.(1)                              7,200
   800,000    PAREXEL International Corp.(1)(2)                 22,450
   50,000     Romac International, Inc.(1)                         978
   220,000    Wackenhut Corrections Corp.(1)                     3,465
                                                              --------
                                                                41,839
                                                              --------

COMMUNICATIONS EQUIPMENT--6.9%
   406,400    Boston Technology, Inc.(1)                         8,128
   300,000    Coherent Communications
                 Systems Corp.(1)                                4,987
   650,000    P-COM, Inc.(1)                                    18,444
   213,100    PairGain Technologies, Inc.(1)                     5,527
   600,000    Teledata Communications(1)(2)                     13,312
                                                              --------
                                                                50,398
                                                              --------

COMMUNICATIONS SERVICES--2.8%
   286,000    Pacific Gateway Exchange, Inc.(1)                  6,900
   960,000    Tel-Save Holdings, Inc.(1)                        13,560
                                                              --------
                                                                20,460
                                                              --------

COMPUTER PERIPHERALS--4.9%
   350,000    Advanced Digital Information Corp.(1)              5,709
   300,000    Applied Magnetics Corp.(1)                         7,537
   310,000    Innovex, Inc.                                      9,862
   120,000    Network Appliances, Inc.(1)                        3,465
   300,000    RadiSys Corp.(1)(2)                                8,794
                                                              --------
                                                                35,367
                                                              --------

Shares                    ($ in Thousands)                      Value
- ------------------------------------------------------------------------

COMPUTER SOFTWARE & SERVICES--14.3%
   380,000    CBT Group Plc ADR(1)                            $ 18,525
   390,000    HBO & Co.                                         20,841
   460,000    HCIA(1)(2)                                         9,574
   150,000    Intelligroup, Inc.(1)                              1,500
   130,000    Keane, Inc.(1)                                     6,029
   145,000    Manugistics Group, Inc.(1)                         7,794
   415,000    McAfee Associates, Inc.(1)                        23,136
   20,900     Pomeroy Computer Resources, Inc.(1)                  502
   450,000    Transaction Systems Architects, Inc.(1)           13,416
   150,000    Vantive Corp.(1)                                   2,991
                                                              --------
                                                               104,308
                                                              --------

CONSUMER PRODUCTS--2.1%
   600,000    NBTY, Inc.(1)(2)                                  11,287
   80,000     Nu Skin Asia Pacific Inc.(1)                       2,080
   175,000    USA Detergents, Inc.(1)                            2,012
                                                              --------
                                                                15,379
                                                              --------

ELECTRICAL & ELECTRONIC
COMPONENTS--8.6%
   502,500    ANADIGICS, Inc.(1)                                14,070
   150,000    Cymer, Inc.(1)                                     6,159
   378,000    Jabil Circuit, Inc.(1)                            18,262
   170,000    Micrel, Inc.(1)                                    7,374
   520,000    Vitesse Semiconductor Corp.(1)                    16,477
                                                              --------
                                                                62,342
                                                              --------
ENERGY (PRODUCTION & MARKETING)--1.0%
   340,000    Petroleum Securities
      Australia Ltd. ADR(1)                                      7,374
                                                              --------
ENERGY (SERVICES)--6.9%
   330,000    Global Marine Inc.(1)                              6,641
   425,000    Hvide Marine, Inc.(1)                              7,225
   800,000    Marine Drilling Companies, Inc.(1)                12,700
   600,000    Noble Drilling Corp.(1)                           10,425
   375,000    Trico Marine Services, Inc.(1)                    13,266
                                                              --------
                                                                50,257
                                                              --------
ENVIRONMENTAL SERVICES--1.8%
   400,000    USA Waste Services, Inc.(1)                       13,100
                                                              --------

FOOD & BEVERAGE--1.3%
   400,000    Morningstar Group Inc.(1)                          9,750
                                                              --------

See Notes to Financial Statements


8    Schedule of Investments                        American Century Investments


Shares                    ($ in Thousands)                      Value
- ------------------------------------------------------------------------

FURNITURE & FURNISHINGS--2.0%
   447,500    Miller (Herman), Inc.                           $ 14,460
                                                              --------

HEALTHCARE--4.4%
   345,000    OccuSystems, Inc.(1)                               7,051
   250,000    Pediatrix Medical Group Inc.(1)                    8,250
   300,000    Quorum Health Group, Inc.(1)                       9,300
   130,000    Renal Care Group Inc.(1)                           3,949
   110,000    Total Renal Care Holdings, Inc.(1)                 3,534
                                                              --------
                                                                32,084
                                                              --------

LEISURE--1.8%
   210,000    Imax Corporation(1)                                7,534
   250,000    Signature Resorts(1)                               5,531
                                                              --------
                                                                13,065
                                                              --------

MACHINERY & EQUIPMENT--2.4%
   265,000    DT Industries, Inc.                                6,956
   575,000    U.S. Rentals, Inc.(1)                             10,925
                                                              --------
                                                                17,881
                                                              --------

MEDICAL EQUIPMENT & SUPPLIES--1.2%
   300,000    Spine-Tech, Inc.(1)                                8,662
                                                              --------

PHARMACEUTICALS--4.1%
   661,000    Capstone Pharmacy Services, Inc.(1)                5,556
   320,000    Kos Pharmaceuticals, Inc.(1)                       7,240
   305,000    NCS HealthCare, Inc. Cl A(1)                       6,977
   400,000    Omnicare, Inc.                                     9,750
                                                              --------
                                                                29,523
                                                              --------

PRINTING & PUBLISHING--1.5%
   450,000    Consolidated Graphics, Inc.(1)                    10,969
                                                              --------

RESTAURANTS--0.3%
   90,000     Rainforest Cafe, Inc.(1)                           2,132
                                                              --------

RETAIL (GENERAL MERCHANDISE)--1.0%
   270,000    Family Dollar Stores, Inc.                         7,054
                                                              --------

RETAIL (SPECIALTY)--4.5%
   780,000    Finish Line, Inc.(1)                               8,044
   270,000    MSC Industrial Direct Co., Inc.(1)                 8,302
   400,000    Pacific Sunwear of California(1)                  12,600
   240,000    Wilmar Industries, Inc.(1)                         4,050
                                                              --------
                                                                32,996
                                                              --------

See Notes to Financial Statements


Shares                    ($ in Thousands)                      Value
- ------------------------------------------------------------------------

TOTAL COMMON STOCKS--90.1%                                    $656,085
                                                              --------
  (Cost $662,332)

TEMPORARY CASH INVESTMENTS(3)

   $13,100 par value FHLMC Discount Note,
       5.39%, 5/19/97                                           13,065

   Repurchase Agreement, Goldman Sachs & Co., Inc.,
       (U.S. Treasury obligations), in a joint trading
       account at 5.29%, dated 4/30/97,
       due 5/1/97 (Delivery value $23,503)                      23,500

   Repurchase Agreement, J.P. Morgan Securities, Inc.,
       (U.S. Treasury obligations), in a joint trading
       account at 5.375%, dated 4/30/97,
       due 5/1/97 (Delivery value $35,305)                      35,300
                                                              --------

TOTAL TEMPORARY CASH INVESTMENTS--9.9%                          71,865
  (Cost $71,865)                                              --------

TOTAL INVESTMENT SECURITIES--100.0%                           $727,950
  (Cost $734,197)                                             ========


Notes to Schedule of Investments

ADR = American Depositary Receipt
FHLMC = Federal Home Loan Mortgage Corporation
(1)  Non-income producing.
(2)  Affiliated  Company:  represents  ownership  of at least  5% of the  voting
     securities of the issuer and is, therefore,  an affiliate as defined in the
     Investment  Company  Act  of  1940.  (See  Note  4 in  Notes  to  Financial
     Statements for a summary of  transactions  for each issuer who is or was an
     affiliate at or during the six months ended April 30, 1997.)
(3)  The  rates  for U.S.  Government  Agency  discount  notes  are the yield to
     maturity at April 30, 1997.


Semiannual Report                                   Schedule of Investments    9

<TABLE>
<CAPTION>
                      STATEMENT OF ASSETS AND LIABILITIES

APRIL 30, 1997 (UNAUDITED)

ASSETS                                                   ($ in Thousands Except Per-Share Amount)
<S>                                                                                          <C> 
Investment securities, at value (identified cost of $734,197) (Note 3)...................$727,950
Cash..........................................................................................373
Receivable for investments sold............................................................11,415
Dividends and interest receivable..............................................................10
                                                                                        ---------
                                                                                          739,748
                                                                                        ---------

LIABILITIES
Disbursements in excess of demand deposit cash................................................243
Payable for investments purchased..........................................................16,013
Payable for capital shares redeemed............................................................69
Accrued management fees (Note 2)..............................................................601
Other liabilities...............................................................................1
                                                                                        ---------
                                                                                           16,927
                                                                                        ---------
Net Assets Applicable to Outstanding Shares..............................................$722,821
                                                                                        =========

CAPITAL SHARES, $0.01 PAR VALUE (In Thousands)
Authorized ...............................................................................200,000
                                                                                        =========

Outstanding ...............................................................................38,258
                                                                                        =========

Net Asset Value Per Share .................................................................$18.89
                                                                                        =========

NET ASSETS CONSIST OF:
Capital (par value and paid in surplus)..................................................$752,413
Undistributed net investment loss.........................................................(2,943)
Accumulated undistributed net realized loss on investment transactions...................(20,402)
Net unrealized depreciation on investments (Note 3).......................................(6,247)
                                                                                        ---------
                                                                                         $722,821
                                                                                        =========
</TABLE>

See Notes to Financial Statements


10   Statement of Assets and Liabilities            American Century Investments

<TABLE>
<CAPTION>
                                         STATEMENT OF OPERATIONS

FOR THE SIX MONTHS ENDED APRIL 30, 1997 (UNAUDITED)

INVESTMENT INCOME                                                                ($ in Thousands)

Income:
<S>                                                                                    <C>       
Interest...............................................................................$    1,123
Dividends......................................................................................65
                                                                                       ----------
                                                                                            1,188
                                                                                       ----------
Expenses (Note 2):
Management fees.............................................................................4,126
Directors' fees and expenses....................................................................5
                                                                                       ----------
                                                                                            4,131
                                                                                       ----------

Net investment loss.......................................................................(2,943)
                                                                                       ----------

REALIZED AND UNREALIZED LOSS
ON INVESTMENTS (NOTE 3)

Net realized loss on investments                                                         (19,307)
Change in net unrealized appreciation on investments....................................(202,854)
                                                                                       ----------

Net realized and unrealized loss
on investments..........................................................................(222,161)
                                                                                       ----------

Net Decrease in Net Assets
Resulting from Operations..............................................................$(225,104)
                                                                                       ==========
</TABLE>

See Notes to Financial Statements


Semiannual Report                                   Statement of Operations   11


<TABLE>
<CAPTION>
                                        STATEMENTS OF CHANGES IN NET ASSETS

SIX MONTHS ENDED APRIL 30, 1997 (UNAUDITED)
AND YEAR ENDED OCTOBER 31, 1996

Increase (Decrease) in Net Assets                                                  1997               1996

OPERATIONS                                                                            ($ in Thousands)

<S>                                                                            <C>                <C>      
Net investment loss............................................................$  (2,943)         $ (5,739)
Net realized gain (loss) on investments..........................................(19,307)           25,992
Change in net unrealized appreciation on investments............................(202,854)           51,469
                                                                               ---------         ---------
Net increase (decrease) in net assets resulting from operations.................(225,104)           71,722
                                                                               ---------         ---------


DISTRIBUTIONS TO SHAREHOLDERS
From net realized gains on investment transactions...............................(27,036)          (48,106)
                                                                               ---------         ---------

CAPITAL SHARE TRANSACTIONS
Proceeds from shares sold.........................................................89,942           242,811
Proceeds from reinvestment of distributions.......................................27,030            48,106
Payments for shares redeemed......................................................(7,761)           (9,895)
                                                                               ---------         ---------

Net increase in net assets from capital share transactions.......................109,211           281,022
                                                                               ---------         ---------

Net increase (decrease) in net assets...........................................(142,929)          304,638

NET ASSETS
Beginning of period..............................................................865,750           561,112
                                                                               ---------         ---------
End of period...................................................................$722,821          $865,750
                                                                               =========         =========
Undistributed net investment loss...............................................$ (2,943)          $    --
                                                                               =========         =========

TRANSACTIONS IN SHARES OF THE FUND (In Thousands)
Sold ..............................................................................3,892            10,014
Issued in reinvestment of distributions............................................1,126             2,075
Redeemed............................................................................(332)             (413)
                                                                               ---------         ---------
Net increase.......................................................................4,686            11,676
                                                                               =========         =========
</TABLE>

See Notes to Financial Statements


12   Statements of Changes in Net Assets            American Century Investments


                         NOTES TO FINANCIAL STATEMENTS

APRIL 30, 1997 (UNAUDITED)

1. ORGANIZATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

ORGANIZATION--American   Century  Mutual  Funds,   Inc.  (the   Corporation)  is
registered under the Investment  Company Act of 1940 as an open-end  diversified
management  investment  company.  Giftrust  (the  Fund) is one of the  seventeen
series of funds issued by the Corporation. The Fund's investment objective is to
seek capital  growth by  investing  primarily in common  stocks.  The  following
significant  accounting  policies  related  to the Fund are in  accordance  with
accounting policies generally accepted in the investment company industry.

SECURITY  VALUATIONS--Portfolio  securities  traded  primarily  on  a  principal
securities  exchange are valued at the last reported sales price, or the mean of
the  latest  bid and  asked  prices  where no last  sales  price  is  available.
Securities traded  over-the-counter are valued at the mean of the latest bid and
asked prices or, in the case of certain foreign securities, at the last reported
sales price,  depending on local  convention or regulation.  When valuations are
not readily  available,  securities  are valued at fair value as  determined  in
accordance with procedures adopted by the Board of Directors.

SECURITY  TRANSACTIONS--Security  transactions  are  accounted  for on the  date
purchased  or  sold.  Net  realized  gains  and  losses  are  determined  on the
identified cost basis, which is also used for federal income tax purposes.

INVESTMENT  INCOME--Dividend  income less  foreign  taxes  withheld  (if any) is
recorded as of the ex-dividend date.  Interest income is recorded on the accrual
basis and includes amortization of discounts and premiums.

REPURCHASE  AGREEMENTS--The  Fund may  enter  into  repurchase  agreements  with
institutions  the  Fund's  investment   manager,   American  Century  Investment
Management,  Inc. (ACIM),  has determined are creditworthy  pursuant to criteria
adopted by the Board of  Directors.  Each  repurchase  agreement  is recorded at
cost.  The  Fund  requires  that  the  securities   purchased  in  a  repurchase
transaction be transferred to the custodian in a manner sufficient to enable the
Fund to obtain those  securities in the event of a default under the  repurchase
agreement.  ACIM  monitors,  on a  daily  basis,  the  value  of the  securities
transferred  to  ensure  that the  value,  including  accrued  interest,  of the
securities  under each repurchase  agreement is equal to or greater than amounts
owed to the Fund under each repurchase agreement.

JOINT TRADING  ACCOUNT--Pursuant  to an Exemptive Order issued by the Securities
and  Exchange  Commission,  the Fund,  along  with other  registered  investment
companies  having   management   agreements  with  ACIM  and  Benham  Management
Corporation, may transfer uninvested cash balances into a joint trading account.
These  balances  are  invested  in one or more  repurchase  agreements  that are
collateralized by U.S. Treasury or Agency obligations.

INCOME TAX STATUS--It is the policy of the Fund to distribute all taxable income
and  capital  gains to  shareholders  and to  otherwise  qualify as a  regulated
investment  company under provisions of the Internal Revenue Code.  Accordingly,
no provision has been made for federal income taxes.

DISTRIBUTIONS TO SHAREHOLDERS--Distributions to shareholders are recorded on the
ex-dividend  date.  Distributions  from net  investment  income and net realized
gains are declared and paid annually.

The character of distributions  made during the year from net investment  income
or net  realized  gains may differ  from  their  ultimate  characterization  for
federal  income tax purposes.  These  differences  are due to differences in the
recognition  of  income  and  expense  items  for  financial  statement  and tax
purposes.

SUPPLEMENTARY INFORMATION--Certain officers and directors of the Corporation are
also officers and/or  directors,  and, as a group,  controlling  stockholders of
American Century  Companies,  Inc., the parent of the  Corporation's  investment
manager,  ACIM,  the  Corporation's  distributor,  American  Century  Investment
Services,  Inc., and the Corporation's transfer agent, American Century Services
Corporation.

USE OF  ESTIMATES--The  preparation of financial  statements in conformity  with
generally accepted  accounting  principles requires management to make estimates
and assumptions  that affect the reported  amounts of assets and liabilities and
disclosure of  contingent  assets and  liabilities  at the date of the financial
statements,  and the reported  amounts of increases  and decreases in net assets
from operations  during the reporting  period.  Actual results could differ from
those estimates.

- --------------------------------------------------------------------------------
2. TRANSACTIONS WITH RELATED PARTIES

The Corporation has entered into a Management  Agreement with ACIM that provides
the Fund with  investment  advisory  and  management  services in exchange for a
single,  unified  fee.  The  Agreement  provides  that all expenses of the Fund,
except brokerage commissions,  taxes, interest,  expenses of those directors who
are not considered "interested persons" as defined in the Investment Company Act
of 1940 (including  counsel fees) and  extraordinary  expenses,  will be paid by
ACIM.  The fee is computed  daily and paid monthly  based on the Fund's  average
daily closing net assets during the previous  month.  The annual  management fee
for the Fund is 1%.


Semiannual Report                             Notes to Financial Statements   13


                         NOTES TO FINANCIAL STATEMENTS

APRIL 30, 1997 (UNAUDITED)

- --------------------------------------------------------------------------------
3. INVESTMENT TRANSACTIONS

Purchases  and sales of common  stock for the six months  ended April 30,  1997,
were  $597,118,643  and  $525,374,280,  respectively.  As  of  April  30,  1997,
accumulated net unrealized  depreciation on investments,  based on the aggregate
cost of  investments  of  $734,820,046  for  federal  income tax  purposes,  was
$6,869,732,  consisting of unrealized appreciation of $65,325,391 and unrealized
depreciation of $72,195,123.

- --------------------------------------------------------------------------------
4. AFFILIATED COMPANY TRANSACTIONS

A summary  of  transactions  for each  issuer who is or was an  affiliate  at or
during the six months ended April 30, 1997, follows:

<TABLE>
                                       Share                        Realized                          April 30, 1997
                                      Balance       Purchase          Sales          Gain            Share          Market
                                    10/31/1996        Cost            Cost          (Loss)          Balance          Value
- -----------------------------------------------------------------------------------------------------------------------------
ISSUER(1)                                                                  ($ in Thousands)
- -----------------------------------------------------------------------------------------------------------------------------
<S>                                  <C>              <C>            <C>           <C>             <C>              <C>  
ACT Networks, Inc.                        --         $11,990        $11,990    $  (6,184)               --
DONCASTERS plc ADR                        --           9,545             --             --         500,000        $11,250
HCIA--                                23,487          11,106        (2,459)        460,000           9,574
NBTY, Inc.                                --          17,002          8,254          (260)         600,000         11,287
PAREXEL International Corp.               --          15,802             --             --      800,000(2)         22,450
RadiSys Corp.                        541,000          23,889         13,101        (5,084)         300,000          8,794
Teledata Communications                   --          12,999             --             --         600,000         13,312
                                                    --------       --------      ---------                       --------
                                                    $114,714        $44,451      $(13,987)                        $76,667
                                                    ========       ========      =========                       ========

(1)  None of the securities produced income during the period.
(2)  Includes  adjustments  for shares  received  from stock split  and/or stock
     spinoff during the period.
</TABLE>

- --------------------------------------------------------------------------------
5. CORPORATE EVENTS
<TABLE>

The following name changes became effective January 1, 1997:

                           NEW NAMES                                             FORMER NAMES
<S>                        <C>                                                  <C> 
Fund's Issuer:             American Century Mutual Funds, Inc.                   Twentieth Century Investors, Inc.
Fund:                      American Century - Twentieth Century Giftrust         Giftrust Investors
Parent Company:            American Century Companies, Inc.                      Twentieth Century Companies, Inc.
Distributor:               American Century Investment Services, Inc.            Twentieth Century Securities, Inc.
Transfer Agent:            American Century Services Corporation                 Twentieth Century Services, Inc.
</TABLE>

14   Notes to Financial Statements                  American Century Investments

<TABLE>
<CAPTION>
                              FINANCIAL HIGHLIGHTS

For a Share Outstanding Throughout the Years Ended October 31 (except as noted)

                                               1997(1)         1996            1995           1994          1993             1992

PER-SHARE DATA
Net Asset Value,
<S>                                           <C>            <C>             <C>            <C>            <C>             <C>   
Beginning of Period...........................$25.79         $25.63          $20.50         $19.23         $13.57          $12.94
                                            ---------     ---------       ---------      ---------       ---------      ---------

Income From Investment Operations

     Net Investment Loss.......................(0.08)(2)      (0.20)(2)       (0.16)(2)      (0.10)         (0.09)          (0.08)

     Net Realized and Unrealized Gain
     (Loss) on Investment Transactions.........(6.04)          2.46            6.37           3.28           7.18            1.41
                                            ---------     ---------       ---------      ---------       ---------      ---------

     Total From
     Investment Operations.....................(6.12)          2.26            6.21           3.18           7.09            1.33
                                            ---------     ---------       ---------      ---------       ---------      ---------

Distributions

     From Net Realized Gains on
     Investment Transactions...................(0.78)         (2.10)          (1.08)         (1.91)         (1.42)          (0.70)

     Distributions in Excess
     of Net Realized Gains......................--            --              --             --             (0.01)          --
                                            ---------     ---------       ---------      ---------       ---------      ---------

     Total Distributions.......................(0.78)         (2.10)          (1.08)         (1.91)         (1.43)          (0.70)
                                            ---------     ---------       ---------      ---------       ---------      ---------

Net Asset Value, End of Period................$18.89         $25.79          $25.63         $20.50         $19.23          $13.57
                                            =========     =========       =========      =========       =========      =========

     Total Return(3)..........................(24.36)%         9.72%          32.52%         18.75%         55.84%          10.32%

RATIOS/SUPPLEMENTAL DATA

Ratio of Operating Expenses
to Average Net Assets........................1.00%(4)         0.98%           0.98%          1.00%           1.00%          1.00%

Ratio of Net Investment Loss
to Average Net Assets.......................(0.71)(4)       (0.80)%         (0.70)%        (0.70)%         (0.70)%        (0.70)%

Portfolio Turnover Rate...........................68%          121%            105%           115%            143%           134%

Average Commission Paid per
Investment Security Traded....................$0.0263       $0.0230         $0.0260          --(5)           --(5)          --(5)

Net Assets, End
of Period (in millions)..........................$723          $866            $561           $266            $154            $78

(1)  Six months ended April 30, 1997 (unaudited).

(2)  Computed using average shares outstanding throughout the period.

(3)  Total  return   assumes   reinvestment   of  dividends  and  capital  gains
     distributions, if any. Total returns for periods less than one year are not
     annualized.

(4)  Annualized.

(5)  Disclosure of average  commission  paid per investment  security traded was
     not required prior to the year ended October 31, 1995.
</TABLE>

See Notes to Financial Statements


Seminnual Report                                       Financial Highlights   15


                             BACKGROUND INFORMATION

INVESTMENT PHILOSOPHY AND POLICIES

The  Twentieth  Century Group offers nine equity funds that invest in the stocks
of growing  companies,  both  domestically and  internationally.  The philosophy
behind these growth funds  focuses on three  important  principles.  First,  the
funds seek to own  successful  companies,  which we define as those with growing
earnings  and  revenues.  Second,  we attempt to keep the funds fully  invested,
regardless of short-term market activity. Experience has shown that market gains
can occur in  unpredictable  spurts and that  missing  those  opportunities  can
significantly  limit the  potential  for gain.  Third,  the funds are managed by
teams, rather than by one "star." We believe this allows us to make better, more
consistent management decisions.

In  addition to these  principles,  each fund has its own  investment  policies.
TWENTIETH  CENTURY  GIFTRUST  generally  invests  in  the  securities  of  small
companies with  accelerating  growth.  Shares of Giftrust can be given only as a
gift, and all  investments  must remain in the fund for a minimum of 10 years or
until the recipient reaches the age of majority, whichever is later. Giftrust is
a volatile investment with high long-term growth potential.

COMPARATIVE INDICES

The  following  indices  are used in the  report  to  serve as fund  performance
comparisons. They are not investment products available for purchase.

The S&P 500 is a capitalization-weighted  index of the stocks of the 500 largest
publicly traded U.S. companies.  Created by Standard & Poor's Corporation, it is
considered to be a broad measure of U.S. stock market performance.

The NASDAQ  COMPOSITE  INDEX is a market  capitalization  price-only  index that
reflects the aggregate  performance  of domestic  common stocks traded "over the
counter" on the regular Nasdaq market, as well as national market  system-traded
foreign  common  stocks and American  Depositary  Receipts.  It is considered to
represent the performance of smaller  capitalization  and  growth-oriented  U.S.
stocks.

The RUSSELL 2000 INDEX was created by the Frank Russell Company. It measures the
performance  of the 2,000  smallest of the 3,000  largest  publicly-traded  U.S.
companies,  based on total market  capitalization.  The Russell 2000  represents
approximately 10% of the total market capitalization of the top 3,000 companies.
The index is  further  broken  down into two  mutually  exclusive  indices.  The
RUSSELL 2000 GROWTH  INDEX,  used in this report,  measures the  performance  of
those  Russell  2000  companies  with  higher  price-to-book  ratios  and higher
forecasted growth rates.


                          FUND MANAGEMENT TEAM LEADERS
                          Portfolio Manager Glenn Fogle
                          Portfolio Manager John Seitzer


16   Background Information                         American Century Investments


                                    GLOSSARY

Returns

o TOTAL  RETURN  figures  show the overall  percentage  change in the value of a
hypothetical  investment  in  the  fund  and  assume  that  all  of  the  fund's
distributions are reinvested.

o AVERAGE ANNUAL RETURNS  illustrate the annually  compounded returns that would
have produced the fund's cumulative total returns if the fund's  performance had
been  constant  over the  entire  period.  Average  annual  returns  smooth  out
variations  in a fund's  return;  they are not the same as  fiscal  year-by-year
results.  For fiscal year-by-year total returns,  please refer to the "Financial
Highlights" on page 15.

PORTFOLIO STATISTICS

o NUMBER OF  COMPANIES--the  number of different  companies  held by a fund on a
given date.

o PRICE/EARNINGS (P/E) RATIO--a stock value measurement calculated by dividing a
company's stock price by its earnings per share,  with the result expressed as a
multiple  instead  of as a  percentage.  (Earnings  per share is  calculated  by
dividing the after-tax earnings of a corporation by its outstanding shares.)

o PORTFOLIO  TURNOVER--the  percentage of a fund's investment  portfolio that is
replaced during a given time period, usually a year. Actively managed portfolios
tend to have higher  turnover than passively  managed  portfolios  such as index
funds.

o EXPENSE RATIO--the  operating expenses of the fund,  expressed as a percentage
of average net assets.  Shareholders pay an annual fee to the investment manager
for  investment  advisory  and  management  services.  The expenses and fees are
deducted from fund income, not from each shareholder account. (See Note 2 in the
Notes to Financial Statements.)

TYPES OF STOCKS

o  BLUE-CHIP  STOCKS--stocks  of the  most  established  companies  in  American
industry.   They  are  generally  large,   fairly  stable  companies  that  have
demonstrated consistent earnings and usually have long-term growth potential.
Examples include General Electric and Coca-Cola.

o CYCLICAL  STOCKS--generally  considered  to be stocks whose price and earnings
fluctuations  tend to follow the ups and downs of the business  cycle.  Examples
include the stocks of  automobile  manufacturers,  steel  producers  and textile
operators.

o  GROWTH  STOCKS--stocks  of  companies  that  have  experienced  above-average
earnings  growth and appear likely to continue  such growth.  These stocks often
sell at  high  P/E  ratios.  Examples  can  include  the  stocks  of  high-tech,
healthcare and consumer staples companies.

o LARGE-CAPITALIZATION  ("LARGE-CAP")  STOCKS--generally considered to be stocks
of  companies  with a market  capitalization  (the  total  value of a  company's
outstanding  stock) of more than $5  billion.  These tend to be the stocks  that
make up the Dow Jones Industrial Average and the S&P 500.

o MEDIUM-CAPITALIZATION ("MID-CAP") STOCKS--generally considered to be stocks of
companies  with  a  market  capitalization  (the  total  value  of  a  company's
outstanding  stock) of between $1 billion and $5  billion.  These tend to be the
stocks that make up the S&P 400.

o SMALL-CAPITALIZATION  ("SMALL-CAP")  STOCKS--generally considered to be stocks
of  companies  with a market  capitalization  (the  total  value of a  company's
outstanding  stock) of less than $1  billion.  These tend to be the stocks  that
make up the Russell 2000 Index.

o VALUE  STOCKS--generally  considered to be stocks that are  purchased  because
they are relatively inexpensive. These stocks are typically characterized by low
P/E ratios.

STATISTICAL TERMINOLOGY

o PRICE/BOOK RATIO--a stock value measurement calculated by dividing a company's
stock price by its book value per share, with the result expressed as a multiple
instead of as a percentage. (Book value per share is calculated by subtracting a
company's liabilities from its assets, then dividing that value by the number of
outstanding shares.)


Semiannual Report                                                  Glossary   17


[american century logo]
American
Century(sm)

P.O. Box 419200
Kansas City, Missouri
64141-6200

Investor Services:
1-800-345-2021 or 816-531-5575

Automated Information Line:
1-800-345-8765

Telecommunications Device for the Deaf:
1-800-634-4113 or 816-444-3485

Fax: 816-340-7962

Internet: www.americancentury.com


AMERICAN CENTURY MUTUAL FUNDS, INC.


Investment Manager
AMERICAN CENTURY INVESTMENT MANAGEMENT, INC.
Kansas City, Missouri

This report and the financial  statements contained herein are submitted for the
general  information  of our  shareholders.  The  report is not  authorized  for
distribution  to  prospective  investors  unless  preceded or  accompanied by an
effective prospectus.

American Century Investment Services, Inc.


9706           [recycled logo]
SH-BKT-8633       Recycled
<PAGE>
                               SEMIANNUAL REPORT

                            [american century logo]
                                    American
                                  Century(sm)

                                 APRIL 30, 1997

                                   TWENTIETH
                                    CENTURY
                                     GROUP

                                     Select
                                    Heritage
                                     Growth

[front cover]


                               TABLE OF CONTENTS

Report Highlights..........................................................    1
Our Message to You.........................................................    2
Period Overview............................................................    3
Select
     Performance & Portfolio Information...................................    4
     Management Q & A......................................................    5
     Schedule of Investments...............................................    8
     Financial Highlights..................................................   32
Heritage
     Performance & Portfolio Information...................................   11
     Management Q & A......................................................   12
     Schedule of Investments...............................................   15
     Financial Highlights..................................................   33
Growth
     Performance & Portfolio Information...................................   18
     Management Q & A......................................................   19
     Schedule of Investments...............................................   22
     Financial Highlights..................................................   34
Statements of Assets and Liabilities.......................................   25
Statements of Operations...................................................   26
Statements of Changes in Net Assets........................................   27
Notes to Financial Statements..............................................   28
Share Class and Retirement
  Account Information......................................................   35
Background Information
     Investment Philosophy and Policies....................................   36
     Comparative Indices...................................................   36
     Fund Management Team Leaders..........................................   36
Glossary...................................................................   37

     American  Century  Investments  offers you nearly 70 fund choices  covering
stocks, bonds, money markets,  specialty investments and blended portfolios.  To
help you find the  funds  that may meet your  needs,  we have  divided  American
Century funds into three groups based on investment style and objectives.  These
groups, which appear below, are designed to help simplify your fund decisions.

                      American Century Investments--Family of Funds

     Benham Group           American Century Group       Twentieth Century Group

  MONEY MARKET FUNDS          ASSET ALLOCATION &
 GOVERNMENT BOND FUNDS          BALANCED FUNDS                GROWTH FUNDS
DIVERSIFIED BOND FUNDS     CONSERVATIVE EQUITY FUNDS       INTERNATIONAL FUNDS
 MUNICIPAL BOND FUNDS           SPECIALTY FUNDS
                                                                 Select
                                                                Heritage
                                                                 Growth

We welcome your comments or questions about this report.  
See the back cover for ways to contact us by mail, phone or e-mail.

Twentieth  Century and the Benham Group are registered marks of American Century
Services Corporation and Benham Management Corporation,  respectively.  American
Century is a service mark of American Century Services Corporation.

                                                    American Century Investments


                               REPORT HIGHLIGHTS

PERIOD OVERVIEW

o    The U.S. stock market  produced widely  divergent  returns over the period.
     The S&P 500's 14.74% six-month total return continued a three-year trend of
     unusually  strong  performance by large-cap  stocks.  By contrast,  the S&P
     MidCap 400 posted a 6.88% return.

o    Factors that were in the S&P 500's favor included: equity investors seeking
     stability and liquidity; strong economic growth with low inflation; and the
     success of index funds.

SELECT

o    A new portfolio manager, Jean Ledford, and two new investment analysts were
     added to the fund management team.

o    The fund  performed  well for the six months ended April 30,  1997,  with a
     return of 10.96%. That was not enough to catch its benchmark,  the S&P 500,
     which posted a 14.74% total return.  Select's  returns have matched the S&P
     500 so far this calendar year but they lagged the index in late 1996,  when
     profit taking and the market's move to more  defensive  stocks hurt some of
     Select's technology holdings.

o    The fund's  investments in defensive  stocks increased during the period as
     the market cycle matured. Because many pharmaceutical stocks met the fund's
     criteria for a high level of sustainable  growth,  holdings of these stocks
     increased.

HERITAGE

o    The fund posted a 4.80%  return for the six months  ended  April 30,  1997,
     compared  to a return of 6.88% for the S&P MidCap 400.  The fund  surpassed
     most of its  peers  due  mainly  to its  investment  style,  which  is more
     conservative than many mid-cap growth funds.

o    Fund  performance  benefited from holdings in several  industries  that are
     consolidating.  Returns were dampened by the market's tepid response during
     the period to fast growing, medium-capitalization companies.

o    Fund  managers  decreased  holdings  in the  business  services  sector and
     increased holdings in computer software and services during the period.

GROWTH

o    Growth's  total return for the six months ended April 30, 1997,  was 5.13%.
     This  compared  to a return of 14.74% for the S&P 500.  The fund has nearly
     matched the S&P 500 for the calendar year-to-date,  due to a strong rebound
     in technology stocks.

o    Fund managers  increased  holdings in  pharmaceutical  companies during the
     period to take advantage of a new cycle of product introductions.  Holdings
     in computer  networking  stocks were trimmed as these  companies'  earnings
     growth slowed.

                SELECT
           INVESTOR CLASS(1)

Total Returns:         AS OF 4/30/97
   6 Months                   10.96%(2)
   1 Year                     20.54%

Net Assets:             $4.2 billion
   (AS of 4/30/97)

Inception Date:             10/31/58

Ticker Symbol:                 TWCIX


               HERITAGE

Total Returns:         AS OF 4/30/97
   6 Months                    4.80%(2)
   1 Year                      6.01%

Net Assets:             $1.1 billion
   (AS of 4/30/97)

Inception Date:             11/10/87

Ticker Symbol:                 TWHIX


                GROWTH

Total Returns:         AS OF 4/30/97
   6 Months                    5.13%(2)
   1 Year                     13.30%

Net Assets:             $4.4 billion
   (AS of 4/30/97)

Inception Date:             10/31/58

Ticker Symbol:                 TWCGX

(1)  See Share Classes, page 35.
(2)  Not annualized.

Many of the investment  terms in this report are defined in the Glossary on page
37.

Semiannual Report                                       Report Highlights      1


                               OUR MESSAGE TO YOU

         [photograph of James E. Stowers, Jr. and James E. Stowers III]

     April 30,  1997,  marked the end of an eventful  period for the company and
the  Twentieth  Century  growth  funds.  We entered  1997 with a new identity --
AMERICAN CENTURY  INVESTMENTS.  American Century encompasses the skills,  talent
and resources  brought  together  when  Twentieth  Century  Mutual Funds and The
Benham Group merged during 1995 and 1996.

     Changing the company's  name after being known as Twentieth  Century Mutual
Funds for almost 40 years was a significant  step.  Although our core investment
disciplines  remain  unchanged,  the combination of Twentieth Century and Benham
allows us to bring you a full menu of nearly 70 funds.  Our offerings range from
conservative  money  market  funds  carrying  the Benham name to the nine equity
growth funds that still carry the Twentieth Century name and employ our hallmark
growth-oriented investment approach.

     The six-month  period ended April 30, 1997, was  challenging for funds that
did not invest in the largest,  most familiar names in the S&P 500. As investors
sought  size,  stability  and  liquidity,  the S&P 500 and funds that mirror the
index  outperformed  growth funds  investing in smaller  companies  and emerging
industries.  This explains why Select, the most conservative of our three growth
funds, performed best during the period.  Heritage, which invests in the mid-cap
market,  performed in line with small- and mid-cap  stocks while  Growth,  which
seeks out the fastest growing companies in the large-cap  universe,  trailed its
benchmark.

     This environment  highlights the importance of diversifying your portfolio.
At any one time,  one  segment of the market will lead all others and money will
follow  that  performance.  No one can  predict  how long the market  will favor
large,  established  stocks. That is why it is important to maintain exposure to
different-sized stocks and different investment styles.

     We also encourage  investors to not focus on short-term  performance.  Over
the long term,  a growth  strategy can provide the kind of  significant  capital
growth that  builds  wealth.  However,  investors  need  patience to weather the
market's cycles and realize the strategy's potential benefits.

     We have  steadily  refined the growth  discipline  pioneered  at  Twentieth
Century  over the past 25 years,  enabling  our teams to identify  and invest in
businesses  that are among the fastest  growing in the world.  We are  confident
that our approach will continue to reward patient investors who stay the course.

     A large part of helping  investors  remain  patient and  confident in their
funds is providing the best possible information  regularly in a helpful format.
Based on investors'  feedback,  we have  redesigned our  shareholder  reports to
include new features such as a one-page report summary, a glossary,  more charts
and graphs,  and expanded  Management Q&A and background  information  sections.
This report displays the new format.

     We  appreciate  your  confidence  in American  Century and look  forward to
continuing to serve you.

Sincerely,

/s/James E. Stowers, Jr.                 /s/James E. Stowers III
James E. Stowers, Jr.                    James E. Stowers III
Chairman of the Board and Founder        President and Chief Executive Officer

2    Our Message to You                             American Century Investments


                                PERIOD OVERVIEW

WIDELY DIVERGENT RETURNS

     The  six-month  period  ended April 30,  1997,  produced  widely  divergent
returns for U.S.  stock  investors.  In general,  the shares of large  companies
(large-cap stocks),  particularly  relatively stable,  industry-leading firms in
the S&P 500,  significantly  outperformed the shares of faster-growing,  smaller
companies  (mid- and small-cap  stocks).  Value stocks (shares of companies that
are lower  priced)  generally  outperformed  growth  stocks  (those of companies
demonstrating  above-average  earnings  growth)  as  investors  placed  a higher
premium on earnings stability than on earnings growth.

STRONG RETURNS FOR THE S&P 500

     The S&P 500 typically  represents  the large-cap  sector of the U.S.  stock
market.  Many investors  also use the index as a proxy for the U.S.  market as a
whole.  The sustained  advance of the S&P 500 was one of the key success stories
of the period.  The index posted a 14.74%  total  return  during the six months,
continuing  a  three-year  trend  of  unusually  strong  results.  Factors  that
supported the S&P 500's performance included:

     o Investors seeking predictable  earnings and liquidity because they feared
rising interest rates and an economic slowdown. The shares of large,  well-known
firms such as Johnson & Johnson and Microsoft rallied appreciably.

     o Favorable  economic  conditions  (robust  growth and low  inflation)  and
particularly strong earnings growth for large-cap companies.

     o The  popularity  and success of S&P 500 index funds.  With more  investor
dollars  chasing  stocks in the S&P 500,  the prices of those  shares  rose much
faster than the prices of mid- and small-cap stocks.

LOWER RETURNS
FOR AGGRESSIVE
GROWTH STOCKS

     Many  analysts  use the S&P MidCap 400 Index and the Russell  2000 Index to
represent mid- and small-cap stocks, respectively.  As shown in the accompanying
graph, the S&P 500 significantly outperformed the smaller-cap indices.

     While the S&P 500 and its component  companies were considered a relatively
safe haven during the period, many investors viewed high growth companies of all
sizes as too volatile and  unpredictable.  As a result,  the market priced these
stocks  more  conservatively,  weighting  current  earnings  more  heavily  than
projected future  earnings.  Investors also became less willing to pay a premium
for fast-growing technology and healthcare shares.

     The resulting price declines were generally based more on market perception
than on  actual  fundamental  indicators  such as  earnings  and  revenue.  Many
companies  experienced  lower share  prices  despite  continuing  to show strong
operating results. Defensive-minded analysts questioned whether the earnings and
revenue  projections  of mid- and  small-cap  companies  would be realized,  and
investors refused to pay the higher prices these shares have been awarded in the
past.

[line graph - data below]

U.S. STOCK MARKET PERFORMANCE (Growth of $1.00)
For the six months ended April 30, 1997

Value on 4/30/97

S&P 500
$1.15

S&P MidCap 400
$1.07

Russell 2000
$1.02

DATE           S&P 500        S&P 400      RUSSELL 2000

10/31/96       $1.00           $1.00          $1.00
11/30/96       $1.07           $1.06          $1.04
12/31/96       $1.06           $1.06          $1.07
1/31/97        $1.12           $1.10          $1.09
2/28/97        $1.13           $1.09          $1.06
3/31/97        $1.08           $1.04          $1.01
4/30/97        $1.15           $1.07          $1.02

S&P 500......................................14.74%
S&P MidCap 400................................6.88%
Russell 2000..................................1.61%

Source: Lipper Analytical Services, Inc.

Semiannual Report                                         Period Overview      3

<TABLE>
<CAPTION>
                                     SELECT

TOTAL RETURNS AS OF APRIL 30, 1997

                                               AVERAGE ANNUAL RETURNS

                     6 MONTHS    1 YEAR     3 YEARS    5 YEARS   10 YEARS   LIFE OF FUND

INVESTOR CLASS (inception 6/30/71)(1)

<S>                   <C>        <C>        <C>        <C>        <C>          <C>   
   SELECT.........    10.96%     20.54%     15.67%     11.35%     10.40%       16.71%

   S&P 500........    14.74%     25.10%     24.08%     17.07%     14.10%       12.62%

INSTITUTIONAL CLASS (inception 3/14/97)

   SELECT..................................................................     2.50%

   S&P 500.................................................................     1.50%
</TABLE>

(1) This inception date corresponds with the management company's implementation
of its current investment philosophy and practices.

See pages  35-37  for more  information  about  share  classes,  the S&P 500 and
returns.


[line graph - data below]

GROWTH OF $10,000 OVER 20 YEARS (Investor Class)

$10,000 investment made 4/30/97

Value on 4/30/97:

Select
$331,138

S & P 500
$176,417

DATE                 SELECT          S & P 500

4/30/77             $10,000          $10,000
4/30/78             $14,419          $10,342
4/30/79             $18,552          $11,452
4/30/80            $24,081           $12,633
4/30/81             $40,330          $16,579
4/30/82             $36,357          $15,366
4/30/83             $66,469          $22,888
4/30/84            $59,917           $23,268
4/30/85             $68,432          $27,370
4/30/86             $98,208          $37,274
4/30/87            $123,166          $47,165
4/30/88            $110,594          $44,128
4/30/89            $129,971          $54,179
4/30/90            $150,658          $59,836
4/30/91            $174,929          $70,344
4/30/92            $193,445          $80,229
4/30/93            $205,839          $87,623
4/30/94            $213,900          $92,290
4/30/95            $229,150         $108,364
4/30/96            $274,717         $141,019
4/30/97            $331,138         $176,417

Past  performance  does not  guarantee  future  results.  Investment  return and
principal  value will fluctuate,  and redemption  value may be more or less than
original  cost.  Data quoted is for Investor Class only;  performance  for other
classes will vary due to differences  in fee  structures  (see the Total Returns
table above).

The line representing Select's total return includes operating expenses (such as
transaction  costs and  management  fees) that reduce  returns,  while the total
return line of the S&P 500 does not.

                             PORTFOLIO AT A GLANCE

                                              4/30/97              10/31/96

Number of Companies                             89                    77
Median Price/Earnings Ratio                    24.6                  24.6
Portfolio Turnover                            57%(1)                105%(2)
Expense Ratio (for Investor Class)           1.00%(3)                1.00%

(1)  Six months ended 4/30/97.
(2)  Year ended 10/31/96.
(3)  Annualized.

4    Select                                  American Century Investments


                                     SELECT

MANAGEMENT Q & A

     An interview with Jean Ledford and Chuck Duboc,  portfolio  managers on the
Select  management  team. Jean joined the Select team in January.  She brings 17
years of investment management experience, most recently as lead manager on a $5
billion large-cap portfolio in the Wisconsin state pension plan.

HOW DID SELECT PERFORM?

     Select's total return for the six months ended April 30, 1997 was 10.96%, a
favorable  return for the period in  absolute  terms.  However,  in  comparative
terms, the fund underperformed its benchmark, the S&P 500, which posted a 14.74%
total  return.  Select's  returns have matched the S&P 500 so far this  calendar
year but they lagged the index in late 1996. (For a more extensive discussion of
the market environment, see the Period Overview on page 3.)

WHAT HAPPENED IN LATE 1996?

     The last two  months of the year were  marked  by  profit  taking,  as many
investors  sold  stocks with strong 1996  performance  and  retreated  to a more
defensive  position.  Stocks  that are  perceived  to be  sensitive  to changing
economic conditions were sold in favor of those considered to have more immunity
to an economic  slowdown.  Among Select's  holdings,  several technology issues,
such as Cascade Communications and Premisys Communications, declined in price as
investors'  perceptions  turned more negative.  Other  holdings  affected by the
sell-off were consumer giants Wal-Mart Stores and Nike Inc.

     The  fund  was  also  underweighted  relative  to the S&P 500 in  financial
stocks,   which  enjoyed  strong   performance   during  the  period.   We  were
underweighted  in this sector  because we expected the Federal  Reserve to raise
interest rates earlier and higher than it did. Such a move would have negatively
affected earnings at banks and insurance companies.

[bar graph - data below]

SELECT'S ONE-YEAR RETURNS OVER 10 YEARS (1) (Periods ended April 30)

DATE         SELECT(1)      S & P 500

4/88         -10.21%          -6.44%
4/89          17.52%          22.78%
4/90          15.92%          10.44%
4/91          16.11%          17.56%
4/92          10.58%          14.05%
4/93           6.41%           9.22%
4/94           3.92%           5.33%
4/95           7.13%          17.42%
4/96          19.89%          30.13%
4/97          20.54%          25.10%

This chart  illustrates  the fund's  returns over the past 10 years and compares
them with the S&P 500's  returns.  The fund's total  returns  include  operating
expenses,  while the S&P 500's returns do not. See page 36 for a description  of
the index. Past performance is no guarantee of future results.

(1) Investor Class.

Semiannual Report                                                  Select      5


                                     SELECT

WHAT STOCKS ADDED MOST TO RETURNS DURING THE PERIOD?

     The fund's top  performers  were  Microsoft  Corp.  and Intel Corp.,  which
dominate  their  industries  and have  become  popular  with  many  mutual  fund
managers.  We also  achieved  significant  gains by taking  large  positions  in
stocks that are not as widely held.  Warner-Lambert  Co. and Tyco  International
are two examples.

     Warner-Lambert,   a  pharmaceutical   and  consumer  health  company,   won
regulatory  approval  for two new drugs during the period.  These  drugs,  which
combat problems associated with diabetes and high cholesterol, collectively have
a market  potential  of more than $1 billion in sales.  The profit  margins  for
these new products are much higher than those of the over-the-counter health and
beauty aids that  sustained the company  during the new  products'  research and
development  phase.  Anticipation  of higher earnings from the new drugs boosted
the stock price during the period.

     Tyco has been one of the fund's  largest  holdings for several  years.  The
company is a diversified  manufacturer  that leads the world in fire  protection
systems. It also makes disposable medical products and underwater communications
and power  cables.  Tyco's  profit  margins have been rising and its growth rate
accelerating for successive quarters. The stock appreciated during the period as
it  announced   multiple  positive   earnings   surprises  and  several  sizable
acquisitions.  Tyco typifies the kind of  investments  we seek; it benefits from
being a global leader in its industry and its growing market share  continues to
boost earnings.

WHICH STOCKS LOWERED THE FUND'S RETURNS?

     The  shares of  Cascade  Communications,  a computer  services  firm,  were
punished by the market as its sales slowed.  Another  disappointment  was in oil
drilling  stocks,  where  Select's  holdings  included  Reading and Bates Corp.,
Falcon  Drilling  and Diamond  Offshore  Drilling.  The stocks  began the period
strongly  but  corrected  early  this  year  as oil and gas  prices  fell.  Many
investors  feared oil companies  would cut back on exploration  budgets and rent
fewer rigs from these  contract  drilling  firms.  However,  demand for offshore
drilling rigs remains  strong and day rates  continue to increase.  These trends
should continue as long as commodity prices are reasonably stable.

WHAT CHANGES DID YOU MAKE TO THE PORTFOLIO DURING THE PERIOD?

     We moved more of the fund's  investments  into defensive  stocks because we
are well into the market cycle. As always,  we continue to look for accelerating
growth and a high level of growth rates. But we are also increasing the emphasis
on the sustainability of earnings growth. Because many pharmaceutical  companies
met these criteria, our holdings of these stocks climbed to

TOP TEN HOLDINGS                           % of fund investments

                                       As of             As of
                                       4/30/97          10/31/96

General Electric Co.                    3.7%              2.6%
Tyco International, Ltd.                3.3%              3.3%
Procter & Gamble Co. (The)              3.1%               --
Microsoft Corp.                         2.9%              2.1%
Coca-Cola Company (The)                 2.4%              1.1%
United Technologies Corp.               2.2%              2.2%
Intel Corp.                             2.2%              3.3%
Textron Inc.                            2.0%              1.7%
Lilly (Eli) & Co.                       2.0%              1.7%
Royal Dutch Petroleum Co.               1.9%               --


TOP FIVE INDUSTRIES                        % of fund investments

                                       As of             As of
                                       4/30/97          10/31/96

Pharmaceuticals                        13.7%              8.6%
Diversified Companies                  11.6%              6.6%
Energy (Production & Marketing)         7.8%              6.1%
Computer Software & Services            6.8%              9.5%
Energy (Services)                       5.5%              9.5%

6    Select                                         American Century Investments


                                     SELECT

nearly 15.0% of the portfolio compared with 8.6% six months earlier. Select also
built positions in food,  beverage and household  products  companies during the
period.

ARE THERE OTHER CHANGES TO SELECT'S MANAGEMENT TEAM?

     Yes, we have added support from seasoned portfolio  analysts.  Rick Petran,
who worked with Jean for 12 years as an investment analyst in Wisconsin,  joined
the team in February.  And Richard Welsh joined the team last year,  moving from
our  quantitative  research team.  Ken Crawford,  who has worked on Select since
mid-1995,  remains on the team. These new resources have improved our ability to
identify and invest in the most attractive large-cap growth stocks.

DO YOU BELIEVE THE LARGE-CAP MARKET IS OVERPRICED?

     While it is true that stock prices for large-cap issues have risen, so have
earnings.  Large-cap stocks have produced more positive earnings  surprises than
their  smaller  brethren  in the  marketplace  and  share  prices  reflect  this
phenomenon.  We  believe  the trend of strong  earnings  will  persist  as these
companies  continue  to reap  the  rewards  of a  decade  of  restructuring  and
increased concentration on their core businesses. Over time, we believe the fund
will benefit not simply from investing in large-cap  stocks,  but from selecting
the companies with continuing high growth rates.

Semiannual Report                                                  Select      7


                            SCHEDULE OF INVESTMENTS
                                     SELECT

APRIL 30, 1997 (UNAUDITED)

Shares                         ($ in Thousands)                         Value
- -----------------------------------------------------------------------------

COMMON STOCKS

AEROSPACE & DEFENSE--5.5%
    373,000     AlliedSignal Inc.                                    $ 26,949
    250,000     Boeing Co.                                             24,656
    775,000     Textron Inc.                                           86,316
  1,250,000     United Technologies Corp.                              94,531
                                                                 ------------
                                                                      232,452
                                                                 ------------
BANKING--5.1%
  1,350,000     Bank of New York Co., Inc. (The)                       53,325
    455,000     BankAmerica Corp.                                      53,178
    300,000     Chase Manhattan Corp.                                  27,787
    315,000     Citicorp                                               35,477
  1,000,000     Northern Trust Corp.                                   44,563
                                                                 ------------
                                                                      214,330
                                                                 ------------
BROADCASTING & MEDIA--0.9%
    800,000     Time Warner Inc.                                       36,000
                                                                 ------------
CHEMICALS & RESINS--2.8%
    400,000     du Pont (E.I.) de Nemours & Co.                        42,450
  1,011,300     Monsanto Co.                                           43,233
  1,070,000     Sherwin-Williams Co.                                   32,368
                                                                 ------------
                                                                      118,051
                                                                 ------------
COMMUNICATIONS EQUIPMENT--2.5%
    650,000     Ericsson (L.M.) Telephone Co. ADR                      21,897
    700,200     Lucent Technologies, Inc.                              41,399
    735,000     Motorola Inc.                                          42,079
                                                                 ------------
                                                                      105,375
                                                                 ------------
COMPUTER PERIPHERALS--0.6%
    500,000     Cisco Systems Inc.(1)                                  25,906
                                                                 ------------
COMPUTER SOFTWARE & SERVICES--6.8%
    536,000     Automatic Data Processing, Inc.                        24,254
    950,000     BMC Software, Inc.(1)                                  41,028
    125,000     Computer Associates
                   International, Inc.                                  6,500
    315,000     Computer Sciences Corp.(1)                             19,687
    975,000     First Data Corp.                                       33,637
  1,000,000     Microsoft Corp.(1)                                    121,563
  1,000,000     Oracle Systems Corp.(1)                                39,812
                                                                 ------------
                                                                      286,481
                                                                 ------------

Shares                         ($ in Thousands)                         Value
- -----------------------------------------------------------------------------

COMPUTER SYSTEMS--2.7%
    500,000     Compaq Computer Corp.(1)                             $ 42,687
    450,000     International Business
                   Machines Corp.                                      72,338
                                                                 ------------
                                                                      115,025
                                                                 ------------
CONSUMER PRODUCTS--5.1%
    400,000     Clorox Company                                         50,950
    400,000     Gillette Company                                       34,000
  1,050,000     Procter & Gamble Co. (The)                            132,038
                                                                 ------------
                                                                      216,988
                                                                 ------------
DIVERSIFIED COMPANIES--11.6%
  1,400,000     Corning Inc.                                           67,550
  1,400,000     General Electric Co.                                  155,225
    700,000     Honeywell Inc.                                         49,438
    500,000     Minnesota Mining &
                   Manufacturing Co.                                   43,500
  2,273,800     Tyco International Ltd.                               138,702
    200,000     Unilever N.V.                                          39,250
                                                                 ------------
                                                                      493,665
                                                                 ------------
ELECTRICAL & ELECTRONIC
COMPONENTS--3.9%
    600,000     Intel Corp.                                            91,875
    800,000     Rockwell International Corp.                           53,200
    225,000     Texas Instruments Inc.                                 20,081
                                                                 ------------
                                                                      165,156
                                                                 ------------
ENERGY (PRODUCTION & MARKETING)--7.8%
    800,000     Apache Corp.                                           27,200
    300,000     British Petroleum Co. p.l.c. ADR                       41,287
    585,000     Coastal Corp. (The)                                    27,787
    900,000     Exxon Corp.                                            50,963
    843,900     Falcon Drilling Co. Inc(1)                             32,279
    450,000     Royal Dutch Petroleum Co.                              81,113
    550,000     Sonat Inc.                                             31,419
    180,000     Texaco Inc.                                            18,990
    250,000     Total-Cie Franc Des ORD                                20,764
                                                                 ------------
                                                                      331,802
                                                                 ------------

See Notes to Financial Statements

8    Select                                         American Century Investments


                            SCHEDULE OF INVESTMENTS
                                     SELECT

APRIL 30, 1997 (UNAUDITED)

Shares                         ($ in Thousands)                         Value
- -----------------------------------------------------------------------------

ENERGY (SERVICES)--5.5%
    950,000     BJ Services Co.(1)                                   $ 44,769
    900,000     Baker Hughes Inc.                                      31,050
    700,000     Diamond Offshore Drilling(1)                           45,062
    350,000     Halliburton Co.                                        24,719
  2,500,000     Reading & Bates Corp.(1)                               55,937
    250,000     Schlumberger Ltd.                                      27,688
     66,100     Western Atlas Inc.(1)                                   4,098
                                                                 ------------
                                                                      233,323
                                                                 ------------
FINANCIAL SERVICES--2.4%
    500,000     Federal Home Loan
                   Mortgage Corporation                                15,938
  1,250,000     Federal National
                   Mortgage Association                                51,406
    600,000     Travelers Group, Inc.                                  33,225
                                                                 ------------
                                                                      100,569
                                                                 ------------
FOOD & BEVERAGE--5.1%
    700,000     Anheuser-Busch Companies, Inc.                         30,012
  1,625,000     Coca-Cola Company (The)                               103,391
  1,600,000     PepsiCo, Inc.                                          55,800
    650,000     Sara Lee Corp.                                         27,300
                                                                 ------------
                                                                      216,503
                                                                 ------------
HEALTHCARE--1.7%
    475,000     Baxter International, Inc.                             22,741
    950,000     Cardinal Health, Inc.                                  50,587
                                                                 ------------
                                                                       73,328
                                                                 ------------
INSURANCE--2.3%
    500,000     Allstate Corp.                                         32,750
    510,000     American International Group, Inc.                     65,535
                                                                 ------------
                                                                       98,285
                                                                 ------------
LEISURE--3.0%
  1,300,000     Carnival Corp. Cl A                                    47,937
    865,000     Disney (Walt) Co.                                      70,930
    125,000     Eastman Kodak Co.                                      10,438
                                                                 ------------
                                                                      129,305
                                                                 ------------
MEDICAL EQUIPMENT & SUPPLIES--0.8%
    500,000     Medtronic, Inc.                                        34,625
                                                                 ------------

Shares                         ($ in Thousands)                         Value
- -----------------------------------------------------------------------------

OFFICE EQUIPMENT--0.5%
    375,000     Xerox Corp.                                         $  23,062
                                                                 ------------
PAPER & FOREST PRODUCTS--2.4%
    429,700     Boise Cascade Corp.                                    14,288
    358,600     Bowater Inc.                                           15,509
    800,000     Kimberly-Clark Corp.                                   41,000
    296,300     Mead Corp. (The)                                       16,630
    325,000     Weyerhaeuser Co.                                       14,869
                                                                 ------------
                                                                      102,296
                                                                 ------------
PHARMACEUTICALS--13.7%
  1,025,000     Abbott Laboratories                                    62,525
  1,040,000     Bristol-Myers Squibb Co.                               68,120
  1,125,000     Johnson & Johnson                                      68,906
    975,000     Lilly (Eli) & Co.                                      85,678
    850,000     Merck & Co., Inc.                                      76,925
     32,000     Novartis ORD                                           42,246
    840,000     Pfizer, Inc.                                           80,640
    290,000     SmithKline Beecham plc ADR                             23,381
    725,000     Warner-Lambert Co.                                     71,050
                                                                 ------------
                                                                      579,471
                                                                 ------------
RESTAURANTS--0.8%
    650,000     McDonald's Corp.                                       34,856
                                                                 ------------
RETAIL (FOOD & DRUG)--1.1%
  1,000,000     Walgreen Co.                                           46,000
                                                                 ------------
RETAIL (GENERAL MERCHANDISE)--1.0%
  1,550,000     Wal-Mart Stores, Inc.                                  43,788
                                                                 ------------
RETAIL (SPECIALTY)--0.5%
    330,000     Home Depot, Inc.                                       19,140
                                                                 ------------
TOBACCO--1.6%
  1,775,000     Philip Morris Companies Inc.                           69,891
                                                                 ------------
TOTAL COMMON STOCKS--97.7%                                          4,145,673
                                                                 ------------
   (Cost $3,291,960)

See Notes to Financial Statements

Semiannual Report                                                  Select      9


                            SCHEDULE OF INVESTMENTS
                                     SELECT

APRIL 30, 1997 (UNAUDITED)

Principal Amount               ($ in Thousands)                         Value
- -----------------------------------------------------------------------------

TEMPORARY CASH INVESTMENTS(2)

       $24,675 par value FNMA Discount Note,
           5.38%, 5/5/97                                            $  24,660

       $25,000 par value FNMA Discount Note,
           5.38%, 5/15/97                                              24,948

       Repurchase Agreement, Goldman Sachs
           & Co., Inc., (U.S. Treasury obligations),
           in a joint trading account at 5.29%,
           dated 4/30/97, due 5/1/97
           (Delivery value $48,707)                                    48,700
                                                                 ------------
TOTAL TEMPORARY
CASH INVESTMENTS--2.3%                                                 98,308
                                                                 ------------
   (Cost $98,308)

TOTAL INVESTMENT SECURITIES--100.0%                                $4,243,981
                                                                 ============
   (Cost $3,390,268)

FORWARD FOREIGN CURRENCY CONTRACTS

          Contracts            Settlement                         Unrealized
           to Sell                Dates            Value             Gain
   ----------------------   ----------------  --------------    --------------
      92,720,000  FRF            6/30/97          $15,976             $ 3
      48,256,000  CHF            6/30/97           33,023              87
                                              --------------    --------------
                                                  $48,999             $90
                                              ==============    ==============
(Value on Settlement Date $49,089)

NOTES TO SCHEDULE OF INVESTMENTS

ADR = American Depositary Receipt
CHF = Swiss Franc
FNMA = Federal National Mortgage Association
FRF = French Franc
ORD = Foreign Ordinary Share

(1)  Non-income producing.

(2)  The  rates  for U.S.  Government  Agency  discount  notes  are the yield to
     maturity at April 30, 1997.

See Notes to Financial Statements

10   Select                                         American Century Investments

<TABLE>
<CAPTION>
                                    HERITAGE


TOTAL RETURNS AS OF APRIL 30, 1997

                                                 AVERAGE ANNUAL RETURNS

                                6 MONTHS    1 YEAR     3 YEARS    5 YEARS  LIFE OF FUND(1)

<S>                               <C>        <C>       <C>        <C>          <C>   
   HERITAGE..................     4.80%      6.01%     11.95%     12.96%       15.27%
   S&P MidCap 400............     6.88%     10.13%     16.21%     14.56%       18.32%   (2)

(1)  Inception was November 10, 1987.

(2)  For the period from  11/30/87  (the date nearest the fund's  inception  for
     which data are available) to 4/30/97.
</TABLE>

See pages 36 and 37 for more  information  about  the  comparative  indices  and
returns.


[line graph - data below]

GROWTH OF $10,000 OVER LIFE OF FUND

Value on 4/30/97:

S&P MidCap 400
$48,757

S&P 500
$46,169

Heritage
$38,860

DATE                HERITAGE         S & P 500         S & P 400

11/30/87            $10,000          $10,000           $10,000
4/30/88             $12,095          $11,548           $12,238
4/30/89             $14,857          $14,179           $15,036
4/30/90             $16,201          $15,659           $16,434
4/30/91             $18,314          $18,409           $20,584
4/30/92             $21,128          $20,996           $24,709
4/30/93             $24,470          $22,931           $28,292
4/30/94             $27,685          $24,152           $31,067
4/30/95             $29,318          $28,359           $34,108
4/30/96             $36,657          $36,905           $44,257
4/30/97             $38,860          $46,169           $48,757

Past  performance  does not  guarantee  future  results.  Investment  return and
principal  value will fluctuate,  and redemption  value may be more or less than
original cost.

The line representing  Heritage's total return includes operating expenses (such
as transaction  costs and management fees) that reduce returns,  while the total
return lines of the indices do not.

PORTFOLIO AT A GLANCE

                                              4/30/97              10/31/96

Number of Companies                             92                    92
Median Price/Earnings Ratio                    20.3                  21.4
Portfolio Turnover                            27%(1)                122%(2)
Expense Ratio                                1.00%(3)                0.99%

(1)  Six months ended 4/30/97.
(2)  Year ended 10/31/96.
(3)  Annualized.

Semiannual Report                                                Heritage     11


                                    HERITAGE

MANAGEMENT Q & A

     An interview  with Nancy Prial and Kevin Lewis,  portfolio  managers on the
Heritage management team.

HOW DID HERITAGE PERFORM?

     Heritage  posted a 4.80%  total  return for the six months  ended April 30,
1997,  compared  to a return of 6.88% for the S&P MidCap  400,  an index that is
used as a proxy  for the  performance  of stocks  in the  medium  capitalization
market.

WHY WERE RETURNS FOR THE FUND LOWER THAN THOSE OF ITS BENCHMARK?

     Company size was a big factor in determining stock  performance  during the
period,  with  investor  dollars  chasing the largest  stocks in the market.  On
average,  the  companies in  Heritage's  portfolio are smaller than those in its
benchmark,  which largely  explains its lower return.  Also,  some of the fund's
higher-growth  stocks  declined in price in November  and  December as investors
sought  liquidity.  These  stocks,  which  include  Eagle  Hardware & Garden and
Norrell Corp.,  rebounded  strongly in May when they reported  strong  earnings,
helping to move the fund ahead of the S&P 400 year to date (as of May 31, 1997).

HOW DID THE FUND'S RETURNS FOR THE PERIOD COMPARE TO THOSE OF ITS PEER GROUP?

     The fund was far  ahead of its  peers.  The  average  mid-cap  growth  fund
returned -3.11% for the period, according to Lipper Analytical Services.  Within
the universe of mid-cap growth stock funds, Heritage is relatively conservative.
We manage the fund so that it is well diversified  across industry  sectors;  we
purchase stocks before their prices reflect the  acceleration in earnings we see
arising from improving company fundamentals; and we invest most of the portfolio
in companies that pay dividends. This


[bar graph - data below]

HERITAGE'S ONE-YEAR RETURNS OVER 10 YEARS (Periods ended April 30)

DATE         HERITAGE      S & P MidCap 400

4/88          20.95% (1)      22.38%(1)
4/89          22.84%          22.86%
4/90           9.04%           9.30%
4/91          13.05%          25.25%
4/92          15.36%          20.04%
4/93          15.82%          14.50%
4/94          13.14%           9.81%
4/95           5.90%           9.79%
4/96          25.04%          29.81%
4/97           6.01%          10.13%

This chart  illustrates the fund's returns since its inception and compares them
with the index's returns.  Heritage's total returns include operating  expenses,
while the S&P MidCap 400's returns do not. See page 36 for a description  of the
index. Past performance is no guarantee of future results.

(1) Returns from  11/30/87,  the date nearest to the fund's  inception  date for
which data is available, to 4/30/88.

12   Heritage                                       American Century Investments


                                    HERITAGE

combination  of factors  positioned  the fund to benefit from equity  investors'
more conservative behavior in the face of potentially higher interest rates.

WHAT STOCKS ADDED MOST TO RETURNS DURING THE PERIOD?

     The  fund   successfully   invested  in  companies  that  led  the  way  in
consolidating  their industries.  Life insurance,  banking and oil companies are
some of the areas where the fund has benefited  from this trend.  All three have
been going through a period of  acquisitions  that have reduced  competition and
capacity.  The acquirers  gain economies of scale,  improved  profit margins and
expanded growth rates from their successfully merged businesses.

     Two insurance  companies,  Conseco Inc. and SunAmerica Inc., were among the
fund's  top  performers.   Both  benefited  from  improved   product  sales  and
consolidation.  Earnings per share also were boosted by stock buy-back programs,
which reduce the number of shares in circulation.  In addition, with strong cash
flows, they have been raising their dividends.

     Washington  Mutual  Savings  Bank in Seattle saw its stock price rise as it
successfully  expanded into  California  through  acquisitions.  The company has
strong  management  and has  benefited  from  improved  economic  conditions  in
Washington and California.

     Another  top  performer  in the fund,  Tosco  Corp.,  is one of the largest
independent oil refining companies in the U.S. It also has acquired  competitors
in an industry that has suffered from overcapacity for several years. We believe
that  industry  leaders like Tosco will be able to improve  profitability  going
forward because profit margins are still significantly below previous highs.

WHICH STOCKS NEGATIVELY AFFECTED THE FUND'S PERFORMANCE?

     Fila  Holding SPA, an Italian  retailer  specializing  in sports  clothing,
sustained the largest price decline of any stock in the  portfolio.  The company
grew at above  average  rates in 1996 due to an expansion  in athletic  footwear
stores and sales of Olympics-related  merchandise.  As the company's growth rate
returned   to  a  more   normal   level   this  year,   the  stock   price  fell
disproportionately to its lessened growth rate.

     Many of the  companies  the fund  invests in performed  spectacularly  on a
fundamental  basis  yet  their  stocks  were  punished  by a market  focused  on
large-cap stocks. One example is Technology Solutions,  which writes software to
help companies  automate call centers,  develops  custom  software  packages for
clients and designs  systems that measure  productivity  and track  incoming and
outgoing  calls.  The  company's  earnings  grew 44% for the year ended Feb. 28,
meeting all analyst estimates, and it is a leader in its industry. Yet the price
investors were

TOP TEN HOLDINGS                           % of fund investments

                                       As of             As of
                                       4/30/97          10/31/96

Conseco Inc.                            4.3%              3.2%
Nokia Corp. Cl A ADR                    2.9%              1.9%
Perkin-Elmer Corp.                      2.6%              2.4%
SunAmerica, Inc.                        2.6%              2.2%
Washington Mutual, Inc.                 2.5%              1.9%
Tosco Corp.                             2.5%              1.6%
Reynolds & Reynolds Co.                 2.0%              2.8%
DEKALB Genetics Corp.                   2.0%              1.4%
BMC Industries, Inc.                    1.9%              1.8%
State Street Boston Corp.               1.8%              2.0%

TOP FIVE INDUSTRIES                        % of fund investments

                                       As of             As of
                                      4/30//97          10/31/96

Computer Software & Services            9.3%              7.2%
Energy (Production & Marketing)         8.6%              5.4%
Insurance                               8.6%              5.4%
Communications Equipment                7.5%              9.6%
Electrical & Electronic
  Components                            6.4%              2.7%

Semiannual Report                                                Heritage     13


HERITAGE

willing to pay dropped as they  favored  larger  companies  with  slower  growth
rates.  Technology Solutions remains a significant holding because it has strong
fundamentals and accelerating growth.

WHAT CHANGES DID YOU MAKE TO THE PORTFOLIO DURING THE PERIOD?

     We reduced our  investments  in business  services from 8.00% of the fund's
holdings  at the  beginning  of the  period  to 4.90%  at the  end.  Some of the
business services  companies that were long-time holdings in the fund had become
richly  valued by the  market,  even as the rate of  earnings  acceleration  had
slowed.  We sold these  companies  and replaced  them with other  holdings  with
greater  upside  potential.  An example of a stock we sold is Paychex,  which we
bought at $10 in mid 1994 and sold for between $29 and $37 during the period.

     The  fund's  shift  out  of  business  services  is  representative  of the
continuous evaluation process our team practices. We decide which companies have
matured in their earnings  acceleration  cycle and which are at the beginning of
that  trend.  This  process  forces us to choose  what we believe to be the best
names  within a sector  and sell  others to make room for stocks  with  stronger
growth potential.

     On the buy side,  we  increased  our  investment  in computer  software and
services  companies  to  9.35%  at the  end  of the  period  from  7.20%  at the
beginning. Within this sector, we own mostly computer services firms because, as
corporate  spending on  technology  continues  to rise,  the demand for computer
service and outsourcing  companies is steadily  increasing.  One such holding is
Getronics,  a Dutch firm that  European  companies  have turned to for help with
converting to a common European  currency and with getting  computer  systems to
recognize the year 2000. We were able to buy this  company's  stock at favorable
prices  because  European  investors  were less willing  than  investors in U.S.
markets  to put a high  value on growth  stocks.  The stock  appreciated  partly
because of earnings  growth and partly  because other  investors  recognized the
underlying strength of the business.

WHAT IS YOUR OUTLOOK FOR THE FUND?

     The market  uncertainty  that existed  during the period is actually  quite
good for Heritage and could help the fund going forward. The fund's appreciation
comes from buying the stocks of companies  that are growing more quickly than is
reflected  in the current  stock price.  As investors  flock to the names of the
largest  stocks in the S&P 500,  we are able to buy the stocks of higher  growth
companies at relatively lower prices.

HERITAGE INVESTORS HAVE BEEN ASKED TO APPROVE A DECREASE IN THE PROPORTION OF
DIVIDEND-PAYING COMPANIES TO 60%. HOW WILL THAT AFFECT THE FUND?

     If approved,  the change will increase the available  universe of companies
we can invest in that show the attractive  growth  characteristics  we seek. The
change should not, however, materially increase the fund's volatility because of
several factors that shape our investment decisions. We focus on stocks that are
less volatile and less widely  followed  than the shares  favored by many of our
growth fund peers. We also focus on the valuations  applied to the growth stocks
we buy.  We seek to buy stocks  when they are  selling  at a  discount  to their
long-term  growth  rate.  These  factors,  combined  with the  dividend  policy,
decrease  volatility  for our  investors  while  optimizing  long-term  returns.
(Shareholders of record as of May 16, 1997, are eligible to vote and should have
received a proxy  statement  in the mail.  Please read the  statement  carefully
before voting.)

14   Heritage                                       American Century Investments


                            SCHEDULE OF INVESTMENTS
                                    HERITAGE

APRIL 30, 1997 (UNAUDITED)

Shares                         ($ in Thousands)                         Value
- -----------------------------------------------------------------------------

COMMON STOCKS

AEROSPACE & DEFENSE--3.0%
    325,000     AAR CORP.                                             $ 9,669
    375,000     BE Aerospace, Inc.(1)                                   9,164
    240,000     Precision Castparts Corp.                              12,840
                                                                 ------------
                                                                       31,673
                                                                 ------------
BANKING--4.8%
    250,000     Ahmanson (H.F.) & Co.                                   9,531
    365,000     North Fork Bancorporation, Inc.                        14,463
    540,000     Washington Mutual, Inc.                                26,595
                                                                 ------------
                                                                       50,589
                                                                 ------------
BIOTECHNOLOGY--0.6%
    100,000     Agouron Pharmaceuticals, Inc.(1)                        6,406
                                                                 ------------
BUILDING & HOME IMPROVEMENTS--2.3%
    930,000     Apogee Enterprises, Inc.                               13,892
    479,100     Interface, Inc.                                        10,630
                                                                 ------------
                                                                       24,522
                                                                 ------------
BUSINESS SERVICES & SUPPLIES--4.9%
    200,000     National Computer Systems, Inc.                         5,012
    570,000     Norrell Corp.                                          15,034
     80,000     Paychex, Inc.                                           3,745
  1,025,000     Reynolds & Reynolds Co.                                21,269
    690,000     SITEL Corp.(1)                                          6,814
                                                                 ------------
                                                                       51,874
                                                                 ------------
COMMUNICATIONS EQUIPMENT--7.5%
    480,000     ADC Telecommunications, Inc.(1)                        12,540
    400,000     Newbridge Networks Corp.(1)                            12,700
    480,000     Nokia Corp. Cl A ADR                                   31,020
    290,000     Sensormatic Electronics Corp.                           4,350
    375,000     Tellabs, Inc.(1)                                       14,930
    455,500     Wireless Telecom Group                                  4,384
                                                                 ------------
                                                                       79,924
                                                                 ------------
COMMUNICATIONS SERVICES--0.9%
    170,000     Cincinnati Bell Inc.                                    9,520
                                                                 ------------

Shares                         ($ in Thousands)                         Value
- -----------------------------------------------------------------------------

COMPUTER PERIPHERALS--5.3%
    700,000     BMC Industries, Inc.                                 $ 20,300
    580,000     Inacom Corp.(1)(2)                                     12,724
    300,000     SCI Systems, Inc.(1)                                   18,525
    260,000     Zero Corp.                                              5,070
                                                                 ------------
                                                                       56,619
                                                                 ------------
COMPUTER SOFTWARE & SERVICES--9.3%
    295,000     Adobe Systems Inc.                                     11,505
    515,000     BDM International Inc.(1)                              12,167
    250,000     Cap Gemini ORD                                          8,173
    275,000     Comdisco, Inc.                                          8,731
    460,000     Getronics Geveke N.V. ORD                              13,950
    335,000     HBO & Co.                                              17,902
    400,000     Henry (Jack) & Associates, Inc.                         7,750
    550,000     Spectrum HoloByte, Inc.(1)                              3,334
    605,000     Technology Solutions Co.(1)                            16,108
                                                                 ------------
                                                                       99,620
                                                                 ------------
CONSUMER PRODUCTS--3.5%
     80,000     Adidas AG ORD                                           8,350
    299,300     Fila Holding S.p.A. ADR                                12,945
    625,000     Herbalife International, Inc.                          10,273
    400,000     Stride Rite Corp. (The)                                 5,500
                                                                 ------------
                                                                       37,068
                                                                 ------------
CONTROL & MEASUREMENT--3.8%
    380,000     Perkin-Elmer Corp.                                     27,597
    230,000     Tektronix, Inc.                                        12,449
                                                                 ------------
                                                                       40,046
                                                                 ------------
ELECTRICAL & ELECTRONIC
COMPONENTS--6.4%
    325,000     AVX Technology                                          7,272
    175,000     Charter Power System, Inc.                              4,988
    195,000     Cohu, Inc.                                              4,887
    100,000     Dallas Semiconductor Corp.                              3,650
    248,979     LSI Logic Corp.(1)                                      9,523
    170,000     Micron Technology, Inc.                                 5,993
    750,000     Oak Technology, Inc.(1)                                 6,023
    425,000     Pioneer Standard Electronics, Inc.                      5,153
    120,000     Raychem Corp.                                           7,740
    160,000     STB Systems, Inc.(1)                                    4,130
    250,000     Wyle Electronics                                        8,469
                                                                 ------------
                                                                       67,828
                                                                 ------------

See Notes to Financial Statements

Semiannual Report                                                Heritage     15


                            SCHEDULE OF INVESTMENTS
                                    HERITAGE

APRIL 30, 1997 (UNAUDITED)

Shares                         ($ in Thousands)                         Value
- -----------------------------------------------------------------------------

ENERGY (PRODUCTION & MARKETING)--8.6%
    425,000     Camco International, Inc.                            $ 18,859
    650,000     Lomak Petroleum, Inc.                                  10,969
    335,000     Newpark Resources, Inc.(1)                             15,033
    300,000     Pennzoil Co.                                           14,775
    200,000     Sun Company, Inc.                                       5,475
    895,000     Tosco Corp.                                            26,514
                                                                 ------------
                                                                       91,625
                                                                 ------------
FINANCIAL SERVICES--1.8%
    250,000     State Street Boston Corp.                              19,688
                                                                 ------------
FOOD & BEVERAGE--4.8%
     50,000     Coca-Cola Enterprises, Inc.                             3,019
    330,000     DEKALB Genetics Corp.                                  20,955
    200,000     Earthgrains Company                                    11,450
    770,000     Richfood Holdings, Inc.                                15,689
                                                                 ------------
                                                                       51,113
                                                                 ------------
INSURANCE--8.6%
  1,105,000     Conseco Inc.                                           45,719
    205,000     Loews Corp.                                            18,834
    595,000     SunAmerica, Inc.                                       27,370
                                                                 ------------
                                                                       91,923
                                                                 ------------
MACHINERY & EQUIPMENT--0.9%
    235,000     Cincinnati Milacron Inc.                                4,759
    200,000     DT Industries, Inc.                                     5,250
                                                                 ------------
                                                                       10,009
                                                                 ------------
MEDICAL EQUIPMENT & SUPPLIES--2.5%
    400,000     Advanced Technology
                   Laboratories, Inc.(1)                               13,200
    300,000     AmeriSource Health Corp.(1)                            13,388
                                                                 ------------
                                                                       26,588
                                                                 ------------
OFFICE EQUIPMENT & SUPPLIES--1.0%
    290,000     Avery Dennison Corp.                                   10,658
                                                                 ------------
PAPER & FOREST PRODUCTS--0.8%
    175,000     Union Camp Corp.                                        8,509
                                                                 ------------

Shares                         ($ in Thousands)                         Value
- -----------------------------------------------------------------------------

PHARMACEUTICALS--2.5%
    250,000     Mylan Laboratories                                  $   3,000
    500,000     Omnicare, Inc.                                         12,187
    225,000     Teva Pharmaceutical
                   Industries Ltd. ADR                                 11,363
                                                                 ------------
                                                                       26,550
                                                                 ------------
RETAIL (APPAREL)--4.7%
    350,000     AnnTaylor Stores Corp.(1)                               8,488
    240,000     Gucci Group N.V.                                       16,650
    345,000     Liz Claiborne, Inc.                                    15,611
    245,000     St. John Knits, Inc.                                    9,402
                                                                 ------------
                                                                       50,151
                                                                 ------------
RETAIL (SPECIALTY)--3.6%
    530,000     Eagle Hardware & Garden, Inc.(1)                        9,871
    875,000     Food Lion, Inc. Cl A                                    5,824
    350,000     Hasbro, Inc.                                            8,750
    325,000     Heilig-Meyers Co.                                       4,875
    250,000     Lowe's Companies, Inc.                                  9,500
                                                                 ------------
                                                                       38,820
                                                                 ------------
TRANSPORTATION--0.9%
    380,000     Expeditors International of
                   Washington, Inc.                                     9,571
                                                                 ------------
MISCELLANEOUS--2.4%
    387,500     Miller Industries(1)                                    4,602
    225,000     Timken Co.                                             13,078
    200,000     Valmont Industries, Inc.                                7,937
                                                                 ------------
                                                                       25,617
                                                                 ------------
TOTAL COMMON STOCKS--95.4%                                          1,016,511
                                                                 ------------
   (Cost $815,175)

CONVERTIBLE PREFERRED STOCKS--0.6%

COMPUTER SOFTWARE & SERVICES
    200,000     Vanstar Financing Trust (Acquired
                   9/27/96 through 10/24/96)(3)                         6,475
                                                                 ------------
(Cost $10,274)

See Notes to Financial Statements

16   Heritage                                       American Century Investments


                            SCHEDULE OF INVESTMENTS
                                    HERITAGE

APRIL 30, 1997 (UNAUDITED)

Principal Amount               ($ in Thousands)                         Value
- -----------------------------------------------------------------------------

CONVERTIBLE BONDS

COMPUTER PERIPHERALS--0.7%
$  4,000   Quantum Corp., 5.00%, 3/1/03
              (Acquired 1/29/97 through
              3/17/97, Cost $6,748)(3)                              $   7,790
                                                                 ------------

ELECTRICAL & ELECTRONIC
COMPONENTS--1.2%
  6,000    C-Cube Microsystems, Inc.,
              5.875%, 11/1/05                                           6,023
  7,500    VLSI Technology, Inc.,
              8.25%, 10/1/05                                            7,106
                                                                 ------------
                                                                       13,129
                                                                 ------------
MEDICAL EQUIPMENT & SUPPLIES--1.0%
 10,000    Heartport, Inc., 7.25%,
              5/1/04 (Acquired
              4/15/97, Cost $10,000)(3)                                10,600
                                                                 ------------
TOTAL CONVERTIBLE BONDS--2.9%                                          31,519
                                                                 ------------
   (Cost $31,749)

TEMPORARY CASH INVESTMENTS--1.1%

       Repurchase Agreement, J. P. Morgan
           Securities, Inc., (U.S. Treasury
           obligations), in a joint
           trading account at 5.375%,
           dated 4/30/97, due 5/1/97
           (Delivery value $11,202)                                    11,200
                                                                 ------------
   (Cost $11,200)

TOTAL INVESTMENT SECURITIES--100.0%                                $1,065,705
                                                                 ============
   (Cost $868,398)

FORWARD FOREIGN CURRENCY CONTRACTS

          Contracts            Settlement                         Unrealized
           to Sell                Dates            Value             Gain
    ---------------------   ----------------  --------------    --------------

      11,328,000  DEM            6/30/97          $ 6,580             $ 2
      37,676,000  NLG            6/30/97           19,448              46
                                              --------------    --------------
                                                  $26,028             $48
                                              ==============    ==============
(Value on Settlement Date $26,076)

NOTES TO SCHEDULE OF INVESTMENTS

ADR = American Depositary Receipt
DEM = German Mark
NLG = Netherlands Guilder
ORD = Foreign Ordinary Share

(1)  Non-income producing.

(2)  Affiliated  Company:  represents  ownership  of at least  5% of the  voting
     securities of the issuer and is, therefore,  an affiliate as defined in the
     Investment  Company  Act  of  1940.  (See  Note  5 in  Notes  to  Financial
     Statements for a summary of  transactions  for each issuer who is or was an
     affiliate at or during the six months ended April 30, 1997.)

(3)  Security was purchased  under Rule 144A of the  Securities Act of 1933 and,
     unless registered under the Act or exempted from registration,  may only be
     sold  to  qualified  institutional   investors.   The  aggregate  value  of
     restricted  securities at April 30, 1997,  was $24,865,  which  represented
     2.3% of the net assets of Heritage.

See Notes to Financial Statements

Semiannual Report                                                Heritage     17


<TABLE>
<CAPTION>
                                     GROWTH

TOTAL RETURNS AS OF APRIL 30, 1997

                                         AVERAGE ANNUAL RETURNS

                     6 MONTHS    1 YEAR     3 YEARS    5 YEARS   10 YEARS   20 YEARS

<S>                    <C>       <C>        <C>         <C>       <C>        <C>   
   GROWTH.........     5.13%     13.30%     11.96%      9.57%     11.31%     19.96%
   S&P 500........    14.74%     25.10%     24.08%     17.07%     14.10%     15.43%
</TABLE>

See pages 36 and 37 for more information about the S&P 500 and returns.


[line graph data]

GROWTH OF $10,000 OVER 20 YEARS

$10,000 investment made 4/30/97

Value on 4/30/97:

Growth
$381,024

S & P 500
$176,417

DATE                 GROWTH          S & P 500

4/30/77             $10,000          $10,000
4/30/78             $14,910           10,342
4/30/79             $21,950          $11,452
4/30/80             $29,989          $12,633
4/30/81             $56,532          $16,579
4/30/82             $43,209          $15,366
4/30/83             $70,009          $22,888
4/30/84             $61,012          $23,268
4/30/85             $65,799          $27,370
4/30/86             $98,673          $37,274
4/30/87            $130,547          $47,165
4/30/88            $113,932          $44,128
4/30/89            $138,804          $54,179
4/30/90            $159,606          $59,836
4/30/91            $200,909          $70,344
4/30/92            $241,279          $80,229
4/30/93            $238,001          $87,623
4/30/94            $271,410          $92,290
4/30/95            $289,145         $108,364
4/30/96            $336,311         $141,019
4/30/97            $381,024         $176,417

Past  performance  does not  guarantee  future  results.  Investment  return and
principal  value will fluctuate,  and redemption  value may be more or less than
original cost.

The line representing Growth's total return includes operating expenses (such as
transaction  costs and  management  fees) that reduce  returns,  while the total
return line of the S&P 500 does not.

PORTFOLIO AT A GLANCE

                                              4/30/97              10/31/96

Number of Companies                             63                    64
Median Price/Earnings Ratio                    25.1                  25.9
Portfolio Turnover                            41%(1)                122%(2)
Expense Ratio                                1.00%(3)                1.00%

(1)  Six months ended 4/30/97.
(2)  Year ended 10/31/96.
(3)  Annualized.

18   Growth                                         American Century Investments


                                     GROWTH

MANAGEMENT Q & A

     An interview  with Jim Stowers III,  lead manager of the Growth  management
team.

HOW DID GROWTH PERFORM?

     The fund posted a modest  return for the six months  ended April 30,  1997,
but more than doubled that return year-to-date (as of May 31, 1997). For the six
months ended April 30, 1997, the fund's total return was 5.13%, but for the five
months ended May 31, 1997, the fund's total return was 13.76%.

WHY WAS GROWTH'S  YEAR-TO-DATE  PERFORMANCE (AS OF MAY 31, 1997) HIGHER THAN ITS
PERFORMANCE DURING THE PERIOD?

     Simply put, the year-to-date  return includes May and excludes November and
December.  Late in 1996, the stocks of several of our larger technology holdings
dropped as investors  anticipated  that interest  rates would  increase in 1997.
Many investors  shunned the stocks of rapidly growing  companies,  preferring to
own defensive stocks, such as companies that produce consumer goods. In May, the
sentiment  shifted and many technology  companies'  stocks soared.  We held onto
many of the companies that  performed  poorly late in 1996 because we recognized
their growth  potential did not change,  even though market  sentiment  had. ADC
Telecommunications,  Tellabs, Inc. and Newbridge Networks Corp. are all examples
of stocks that hurt the fund late last year and are boosting  returns now. These
companies  provide  telecommunications  equipment to cable companies,  telephone
companies,  internet  providers  and other  service  providers in the  expanding
information industry.

     We have held true to our discipline of investing in fast growing  companies
with accelerating  earnings,  even though the market does not always reward this
strategy.  Over time, we believe these  companies  will  outperform  the broader
market as investor dollars reward a high rate of earnings growth.


[bar graph - data below]

GROWTH'S ONE-YEAR RETURNS OVER 10 YEARS (Periods ended April 30)

DATE          GROWTH        S & P 500

4/88         -12.73%          -6.44%
4/89          21.83%          22.78%
4/90          14.99%          10.44%
4/91          25.88%          17.56%
4/92          20.09%          14.05%
4/93          -1.36%           9.22%
4/94          14.04%           5.33%
4/95           6.53%          17.42%
4/96          16.31%          30.13%
4/97          13.30%          25.10%

This chart  illustrates  the fund's  returns over the past 10 years and compares
them  with the S&P 500's  returns.  Growth's  total  returns  include  operating
expenses,  while the S&P 500's returns do not. See page 36 for a description  of
the index. Past performance is no guarantee of future results.

Semiannual Report                                                  Growth     19


                                     GROWTH

WHEN DO YOU SELL A STOCK WHOSE PERFORMANCE IS HURTING THE FUND?

     When we are convinced that the  acceleration in earnings and revenue growth
is slowing  and/or when we see an  unfavorable  change in a  company's  business
prospects. While we held onto the telecommunications  providers listed above, we
sold  computer  networking  companies  late  last  year  when  they were slow to
introduce new products and their  earnings per share growth began to decelerate.
We continue to like the technology  sector because of the accelerating  earnings
these  companies  produce,  but we  constantly  monitor which stocks have strong
future prospects and which do not.

WHAT STOCKS ADDED MOST TO RETURNS DURING THE PERIOD?

     As a group,  the insurance  stocks we owned performed well.  These included
Conseco  Inc.,  Travelers  Group Inc. and Allstate  Corp.  The fund's  insurance
holdings  appreciated  for a variety  of  reasons,  but common  themes  included
industry  consolidation  through  acquisitions,  reductions in the frequency and
severity of claims and share buy-back programs. By using income from premiums to
buy shares instead of writing policies,  the companies  reduced  competition and
boosted  profits.  Earnings per share improved as profits  strengthened  and the
amount of outstanding stock declined.

     The stock that contributed most to Growth's  performance for the six months
was First USA Inc., a credit card issuer. We began purchasing the stock in June,
1996, in the mid-$20 range and sold the majority of it earlier this year when it
was  trading  in the upper $40  range.  We began to sell the  stock  after  Ohio
banking giant BancOne announced it was acquiring First USA on Jan. 20.

WHICH STOCKS DISAPPOINTED YOU?

     Computer  networking  stocks Xylan Corp.  and Cisco Systems Inc. were among
the  fund's  poorer   performers.   The  market  punished  these  companies  for
reporting lower revenues than analysts expected.

     First  Data  Corp.  also  suffered  a price  decline  during the period but
remains  a  significant   holding   because  of  its  excellent   prospects  for
accelerating  earnings.  The company  handles credit card processing and account
statements  for credit card  issuers,  such as banks.  We expect this company to
benefit from a long-term consumer trend toward use of debit and credit cards and
away from cash and paper  checks.  Part of the  reason  the  company's  earnings
suffered during the period was capital  spending to address the year 2000 issue,
which all companies relying on computers must face.

TOP TEN HOLDINGS                           % of fund investments

                                       As of             As of
                                       4/30/97          10/31/96

Lilly (Eli) & Co.                       3.9%              1.7%
Conseco Inc.                            3.8%              1.7%
Merck & Co., Inc.                       3.4%              1.4%
Compuware Corp.                         3.4%              1.8%
Tellabs, Inc.                           3.2%              4.9%
Texas Instruments Inc.                  3.1%               --
Allstate Corp.                          3.1%              1.3%
Newbridge Networks Corp.                3.1%              4.5%
Avon Products, Inc.                     2.8%              1.6%
Worldcom Inc.                           2.6%              0.8%

TOP FIVE INDUSTRIES                        % of fund investments

                                       As of             As of
                                       4/30/97          10/31/96

Communications Equipment               12.4%             15.4%
Computer Software & Services           10.7%             12.8%
Insurance                               9.6%              4.9%
Pharmaceuticals                         9.2%              6.7%
Electrical & Electronic
  Components                            8.0%              2.3%

20   Growth                                         American Century Investments


                                     GROWTH

WHAT CHANGES DID YOU MAKE TO THE PORTFOLIO DURING THE PERIOD?

     The team continually evaluates the stocks in which the fund invests to weed
out  companies  that are late in the cycle of  accelerating  earnings and to buy
companies in the early stages of that cycle. Sometimes that results in shifts in
the sector weightings in the fund.

     We increased  Growth's holdings in pharmaceutical  stocks to take advantage
of a new cycle of product  introductions.  Drug companies'  heavy  investment in
research and  development is paying off with many new products coming to market.
These new products,  combined with the favorable demographic trends of the aging
U.S.  population,  give us confidence  that many companies in this industry will
see earnings acceleration.

     We reduced  computer  networking  stocks  during the period for the reasons
cited earlier.

WHAT IS YOUR ROLE ON THE GROWTH FUND TEAM? WHAT IS THE OUTLOOK FOR THE FUND?

     I have  worked  with the  fund on and off  over the past 15 years  and have
rejoined  the team  recently.  Chris Boyd,  who helped  manage the fund for five
years,  left early  this  year.  The team is  composed  of two other  investment
professionals with a combined 14 years of investing experience.

     One of my goals is to keep the fund  focused on the stocks of solid  growth
companies that have a global presence and a strong franchise in their respective
fields.  By sharpening the fund's focus on the large-cap part of the market,  we
intend to improve performance over time.

Semiannual Report                                                  Growth     21


                            SCHEDULE OF INVESTMENTS
                                     GROWTH

APRIL 30, 1997 (UNAUDITED)

Shares                         ($ in Thousands)                         Value
- -----------------------------------------------------------------------------

COMMON STOCKS

AEROSPACE & DEFENSE--0.6%
    250,000     Boeing Co.                                           $ 24,656
                                                                 ------------
BANKING--4.1%
    800,000     Citicorp                                               90,100
    300,000     First Union Corp.                                      25,200
    350,000     Norwest Corp.                                          17,456
  3,232,941     Standard Chartered plc ORD                             49,075
                                                                 ------------
                                                                      181,831
                                                                 ------------
BIOTECHNOLOGY--0.9%
    700,000     Amgen Inc.                                             41,169
                                                                 ------------
BUSINESS SERVICES & SUPPLIES--1.1%
  1,600,000     U.S. Filter Corp.(1)                                   48,600
                                                                 ------------
CHEMICALS & RESINS--1.2%
    700,000     Potash Corp. of Saskatchewan Inc.                      53,813
                                                                 ------------
COMMUNICATIONS EQUIPMENT--12.4%
  3,200,000     ADC Telecommunications, Inc.(1)                        83,600
  1,600,000     Ericsson (L.M.) Telephone Co. ADR                      53,900
  1,295,000     Lucent Technologies, Inc.                              76,567
  4,300,000     Newbridge Networks Corp.(1)                           136,525
    900,000     Nokia Corp. Cl A ADR                                   58,163
  3,500,000     Tellabs, Inc.(1)                                      139,344
                                                                 ------------
                                                                      548,099
                                                                 ------------
COMMUNICATIONS SERVICES--3.5%
    200,000     SBC Communications Inc.                                11,100
    900,000     Teleport Communications
                   Group Inc.(1)                                       25,762
  4,882,500     Worldcom Inc.(1)                                      116,875
                                                                 ------------
                                                                      153,737
                                                                 ------------
COMPUTER PERIPHERALS--0.6%
    300,000     Cisco Systems Inc.(1)                                  15,544
    650,000     Xylan Corp. (1)(2)                                      9,750
                                                                 ------------
                                                                       25,294
                                                                 ------------

Shares                         ($ in Thousands)                         Value
- -----------------------------------------------------------------------------

COMPUTER SOFTWARE & SERVICES--10.7%
  1,660,000     Cambridge Technology
                   Partners, Inc.(1)                                 $ 43,990
  4,000,000     Compuware Corp.(1)                                    151,000
  1,900,000     Concord EFS, Inc.(1)                                   37,762
  1,900,000     First Data Corp.                                       65,550
    600,000     Microsoft Corp.(1)                                     72,938
  1,250,000     Oracle Systems Corp.(1)                                49,766
  1,200,000     SunGard Data Systems Inc.(1)                           53,325
                                                                 ------------
                                                                      474,331
                                                                 ------------
COMPUTER SYSTEMS--3.3%
  1,150,000     Compaq Computer Corp.(1)                               98,181
    300,000     International Business
                   Machines Corp.                                      48,225
                                                                 ------------
                                                                      146,406
                                                                 ------------
CONSUMER PRODUCTS--3.4%
  2,000,000     Avon Products, Inc.                                   123,250
    300,000     Gillette Company                                       25,500
                                                                 ------------
                                                                      148,750
                                                                 ------------
DIVERSIFIED COMPANIES--2.8%
  1,000,000     General Electric Co.                                  110,875
    180,000     Tyco International Ltd.                                10,980
                                                                 ------------
                                                                      121,855
                                                                 ------------
ELECTRICAL & ELECTRONIC
COMPONENTS--8.0%
    600,000     Applied Materials, Inc.(1)                             32,887
    600,000     Intel Corp.                                            91,875
  1,200,000     LSI Logic Corp.(1)                                     45,900
  1,450,000     Microchip Technology Inc.(1)                           45,403
  1,550,000     Texas Instruments Inc.                                138,338
                                                                 ------------
                                                                      354,403
                                                                 ------------
ENERGY (PRODUCTION & MARKETING)--3.1%
    650,000     Amoco Corp.                                            54,356
    200,000     British Petroleum Co. p.l.c. ADR                       27,525
    779,700     Chevron Corp.                                          53,409
                                                                 ------------
                                                                      135,290
                                                                 ------------

See Notes to Financial Statements

22   Growth                                         American Century Investments


                            SCHEDULE OF INVESTMENTS
                                     GROWTH

APRIL 30, 1997 (UNAUDITED)

Shares                         ($ in Thousands)                         Value
- -----------------------------------------------------------------------------

FINANCIAL SERVICES--4.4%
  2,200,000     Federal National
                   Mortgage Association                              $ 90,475
    400,000     First USA, Inc.                                        19,250
  1,500,000     Travelers Group, Inc.                                  83,063
                                                                 ------------
                                                                      192,788
                                                                 ------------
HEALTHCARE--2.3%
    800,000     Oxford Health Plans, Inc.(1)                           52,650
  1,000,000     United HealthCare Corp.                                48,625
                                                                 ------------
                                                                      101,275
                                                                 ------------
INSURANCE--9.6%
    875,000     Ace, Ltd.                                              52,500
  2,100,000     Allstate Corp.                                        137,550
    525,000     American International Group, Inc.                     67,462
  4,063,000     Conseco Inc.                                          168,107
                                                                 ------------
                                                                      425,619
                                                                 ------------
LEISURE--0.8%
   605,000      HFS, Inc.(1)                                           35,846
                                                                 ------------
MEDICAL EQUIPMENT & SUPPLIES--0.8%
  1,050,000     US Surgical Corp.                                      35,963
                                                                 ------------
METALS & MINING--0.5%
    350,000     Reynolds Metals Co.                                    23,756
                                                                 ------------
OFFICE EQUIPMENT & SUPPLIES--2.2%
  1,550,000     Xerox Corp.                                            95,325
                                                                 ------------
PHARMACEUTICALS--9.2%
  1,300,000     Abbott Laboratories                                    79,300
  1,975,000     Lilly (Eli) & Co.                                     173,553
  1,675,000     Merck & Co., Inc.                                     151,588
                                                                 ------------
                                                                      404,441
                                                                 ------------
RETAIL (APPAREL)--1.8%
    850,000     Gucci Group N.V.                                       58,969
    900,000     Nautica Enterprises Inc.(1)                            19,800
                                                                 ------------
                                                                       78,769
                                                                 ------------
RETAIL (FOOD & DRUG)--1.6%
  1,400,000     CVS Corp.                                              69,475
                                                                 ------------

Shares/Principal Amount        ($ in Thousands)                         Value
- -----------------------------------------------------------------------------

RETAIL (SPECIALTY)--3.2%
  2,000,000     CompUSA Inc.(1)                                    $   38,500
  1,350,000     Home Depot, Inc.                                       78,300
    947,700     Tech Data Corp.(1)                                     23,159
                                                                 ------------
                                                                      139,959
                                                                 ------------
TOBACCO--1.4%
  1,550,000     Philip Morris Companies Inc.                           61,031
                                                                 ------------
TOTAL COMMON STOCKS--93.5%                                          4,122,481
                                                                 ------------
   (Cost $3,152,359)

TEMPORARY CASH INVESTMENTS(3)

       $91,000 par value FHLB Discount Notes,
           5.34%-5.39%, 5/1/97 through 5/19/97                         90,829

       $180,000 par value, FNMA Discount Notes,
           5.38%-5.58%, 5/5/97 through 5/23/97                        179,679

       $17,475 par value, SLMA Discount Notes,
           5.28%, 5/1/97                                               17,475
                                                                 ------------

TOTAL TEMPORARY
CASH INVESTMENTS--6.5%                                                287,983
                                                                 ------------
   (Cost $287,983)

TOTAL INVESTMENT SECURITIES--100.0%                                $4,410,464
                                                                 ------------
   (Cost $3,440,342)

FORWARD FOREIGN CURRENCY CONTRACTS

          Contract             Settlement                         Unrealized
           to Sell                Date             Value             Loss
    ---------------------   -----------------  --------------   --------------
      22,194,782  GBP            6/30/97          $36,051            $(43)
                                               ==============   ==============
(Value on Settlement Date $36,008)

See Notes to Financial Statements

Semiannual Report                                                  Growth     23


                            SCHEDULE OF INVESTMENTS
                                     GROWTH

NOTES TO SCHEDULE OF INVESTMENTS

ADR = American Depositary Receipt
FHLB = Federal Home Loan Bank
FNMA = Federal National Mortgage Association
GBP = British Pound
SLMA = Student Loan Marketing Association
ORD = Foreign Ordinary Share

(1)  Non-income producing.

(2)  Affiliated  Company:  represents  ownership  of at least  5% of the  voting
     securities of the issuer and is, therefore,  an affiliate as defined in the
     Investment  Company  Act  of  1940.  (See  Note  5 in  Notes  to  Financial
     Statements for a summary of  transactions  for each issuer who is or was an
     affiliate at or during the six months ended April 30, 1997.)

(3)  The  rates  for U.S.  Government  Agency  discount  notes  are the yield to
     maturity at April 30, 1997.

See Notes to Financial Statements

24   Growth                                         American Century Investments


<TABLE>
<CAPTION>
                      STATEMENTS OF ASSETS AND LIABILITIES

APRIL 30, 1997 (UNAUDITED)                                                           SELECT           HERITAGE          GROWTH

ASSETS                                                                                ($ in Thousands Except Per-Share Amounts)
<S>                                                                                       <C>                <C>               <C>
Investment securities, at value (identified cost of $3,390,268, $868,398,
   $3,440,342, respectively) (Note 3).............................................$    4,243,981  $    1,065,705    $    4,410,464
Cash..............................................................................        1,358              147               491
Receivable for forward foreign currency contracts.................................          90                48               --
Receivable for investments sold...................................................       79,525           14,603            52,363
Receivable for capital shares sold................................................         173                55               190
Dividends and interest receivable.................................................        3,753              953             2,698
                                                                                  --------------  --------------    --------------
                                                                                      4,328,880        1,081,511         4,466,206
                                                                                  --------------  --------------    --------------

LIABILITIES

Disbursements in excess of demand deposit cash....................................        7,622            1,875             7,655
Payable for forward foreign currency contracts....................................          --               --                 43
Payable for investments purchased.................................................       96,200            6,142            51,474
Payable for capital shares redeemed...............................................        2,815              364            28,073
Accrued management fees (Note 2)..................................................        3,293              868             3,478
Other liabilities.................................................................           11                3                12
                                                                                  --------------  --------------    --------------
                                                                                        109,941            9,252            90,735
                                                                                  --------------  --------------    --------------
NET ASSETS........................................................................$    4,218,939  $    1,072,259    $    4,375,471
                                                                                  ==============  ==============    ==============

NET ASSETS CONSIST OF:

Capital (par value and paid in surplus)...........................................$    2,936,936  $      806,055    $    3,038,722
Undistributed net investment income (loss)........................................        4,620            (137)             1,833
Accumulated undistributed net realized gain on
   investment and foreign currency transactions...................................      423,643           68,987           364,837
Net unrealized appreciation on investments and translation
   of assets and liabilities in foreign currencies (Note 3).......................      853,740          197,354           970,079
                                                                                  --------------  --------------    --------------
                                                                                  $    4,218,939  $    1,072,259    $    4,375,471
                                                                                  ==============  ==============    ==============

INVESTOR CLASS ($ AND SHARES IN FULL)
Net assets........................................................................$4,208,281,319 $1,072,258,602     $4,375,471,367
Shares outstanding............................................................... .  100,683,228     89,233,864        190,955,985
Net asset value per share.........................................................$        41.80  $        12.02    $        22.91

INSTITUTIONAL CLASS ($ AND SHARES IN FULL)
Net assets........................................................................$   10,657,882             N/A               N/A
Shares outstanding................................................................       254,922             N/A               N/A
Net asset value per share.........................................................$        41.81             N/A               N/A
</TABLE>

See Notes to Financial Statements

Semiannual Report                    Statements of Assets and Liabilities     25


<TABLE>
<CAPTION>
                            STATEMENTS OF OPERATIONS

FOR THE SIX MONTHS ENDED APRIL 30, 1997 (UNAUDITED)                                  SELECT           HERITAGE          GROWTH

INVESTMENT INCOME                                                                                 ($ in Thousands)

INCOME:
<S>                                                                                       <C>                <C>             <C>  
Dividends (net of foreign taxes withheld of $254, $69 and $408, respectively).....     $ 25,253          $ 4,821          $ 20,315
Interest..........................................................................        2,346              786             4,576
                                                                                  --------------  --------------    --------------
                                                                                         27,599            5,607            24,891
                                                                                  --------------  --------------    --------------

EXPENSES (NOTE 2):
Management fees...................................................................       20,464            5,580            22,930
Directors' fees and expenses......................................................           26                7                28
                                                                                  --------------  --------------    --------------
                                                                                         20,490            5,587            22,958
                                                                                  --------------  --------------    --------------

NET INVESTMENT INCOME.............................................................        7,109               20             1,933
                                                                                  --------------  --------------    --------------

REALIZED AND UNREALIZED GAIN (LOSS)
ON INVESTMENTS AND FOREIGN CURRENCY (NOTE 3)

NET REALIZED GAIN (LOSS) ON:
Investments.......................................................................      422,136           65,798           376,078
Foreign currency transactions.....................................................        4,907            5,442             (122)
                                                                                  --------------  --------------    --------------
                                                                                        427,043           71,240           375,956
                                                                                  --------------  --------------    --------------

CHANGE IN NET UNREALIZED APPRECIATION ON:
Investments.......................................................................      (5,185)         (19,315)         (149,223)
Translation of assets and liabilities in foreign currencies.......................        (322)             (95)              (43)
                                                                                  --------------  --------------    --------------
                                                                                        (5,507)         (19,410)         (149,266)
                                                                                  --------------  --------------    --------------

NET REALIZED AND UNREALIZED GAIN ON INVESTMENTS...................................      421,536           51,830           226,690
                                                                                  --------------  --------------    --------------

NET INCREASE IN NET ASSETS RESULTING FROM OPERATIONS..............................     $428,645          $51,850          $228,623
                                                                                  ==============  ==============    ==============
</TABLE>

See Notes to Financial Statements

26   Statements of Operations                       American Century Investments


<TABLE>
<CAPTION>
                       STATEMENTS OF CHANGES IN NET ASSETS

SIX MONTHS ENDED APRIL 30, 1997 (UNAUDITED)
AND YEAR ENDED OCTOBER 31, 1996                                   SELECT                   HERITAGE                  GROWTH

INCREASE (DECREASE) IN NET ASSETS                           1997         1996         1997         1996          1997         1996

OPERATIONS                                                                             ($ in Thousands)

<S>                                                     <C>           <C>          <C>          <C>          <C>          <C>       
Net investment income (loss)........................... $    7,109    $   21,045   $       20   $    (125)   $    1,933   $  (3,163)
Net realized gain on investments and
     foreign currency transactions.....................    427,043      364,952        71,240       69,544      375,956      104,580
Change in net unrealized appreciation
     on investments and translation of assets
     and liabilities in foreign currencies.............    (5,507)       324,433     (19,410)       34,728    (149,266)      253,622
                                                        ----------    ----------   ----------   ----------   ----------   ----------
Net increase in net assets resulting from operations...    428,645       710,430       51,850      104,147      228,623      355,039
                                                        ----------    ----------   ----------   ----------   ----------   ----------

DISTRIBUTIONS TO SHAREHOLDERS

From net investment income:
     Investor Class....................................   (31,065)      (26,725)      (8,095)      (4,182)     (38,510)     (14,900)
From net realized gains from investment transactions:
     Investor Class....................................  (353,996)     (462,881)     (62,011)     (53,228)     (51,784)    (642,609)
In excess of net realized gain:
     Investor Class....................................        --           --            --           --           --      (16,441)
                                                        ----------    ----------   ----------   ----------   ----------   ----------
Decrease in net assets from distributions..............  (385,061)     (489,606)     (70,106)     (57,410)     (90,294)    (673,950)
                                                        ----------    ----------   ----------   ----------   ----------   ----------

CAPITAL SHARE TRANSACTIONS (NOTE 4)

Net increase (decrease) in net assets from
     capital share transactions........................    136,676     (190,583)        7,364       28,091    (528,282)     (45,559)
                                                        ----------    ----------   ----------   ----------   ----------   ----------

NET INCREASE (DECREASE) IN NET ASSETS..................    180,260        30,241     (10,892)       74,828    (389,953)    (364,470)

NET ASSETS
Beginning of period....................................  4,038,679     4,008,438    1,083,151    1,008,323    4,765,424    5,129,894
                                                        ----------    ----------   ----------   ----------   ----------   ----------
End of period.......................................... $4,218,939    $4,038,679   $1,072,259   $1,083,151   $4,375,471   $4,765,424
                                                        ==========    ==========   ==========   ==========   ==========   ==========
</TABLE>

See Notes to Financial Statements

Semiannual Report                     Statements of Changes in Net Assets     27


                         NOTES TO FINANCIAL STATEMENTS

APRIL 30, 1997 (UNAUDITED)

1. ORGANIZATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

     ORGANIZATION -- American  Century Mutual Funds,  Inc. (the  Corporation) is
registered under the Investment  Company Act of 1940 as an open-end  diversified
management investment company.  American Century - Twentieth Century Select Fund
(Select),  American Century - Twentieth  Century  Heritage Fund (Heritage),  and
American Century - Twentieth  Century Growth Fund (Growth) (the Funds) are three
of the  seventeen  series  of  funds  issued  by  the  Corporation.  The  Funds'
investment  objective is to seek capital growth by investing primarily in equity
securities.  As a matter of fundamental  policy, 80% of the assets of Select and
Heritage  must be  invested in  securities  of  companies  that have a record of
paying  dividends  or  have  committed  themselves  to the  payment  of  regular
dividends,  or  otherwise  produce  income.  On  September  3,  1996,  the Funds
implemented a multiple class structure  whereby each Fund is authorized to issue
three  classes  of  shares:  the  Investor  Class,  the  Advisor  Class  and the
Institutional  Class.  The shares  outstanding  prior to September 3, 1996, were
designated  as  Investor  Class  shares.  The three  classes  of  shares  differ
principally in their respective  shareholder servicing and distribution expenses
and  arrangements.  All shares of each Fund represent an equal pro rata interest
in the  assets of the class to which  such  shares  belong,  and have  identical
voting,  dividend,   liquidation  and  other  rights  and  the  same  terms  and
conditions,  except for class specific  expenses and exclusive rights to vote on
matters affecting only individual  classes.  Sale of the Institutional Class for
Select commenced on March 14, 1997. Sale of the Advisor Class and  Institutional
Class for  Heritage  and  Growth had not  commenced  as of April 30,  1997.  The
following significant accounting policies related to the Funds are in accordance
with accounting policies generally accepted in the investment company industry.

     SECURITY VALUATIONS -- Portfolio securities traded primarily on a principal
securities  exchange are valued at the last reported sales price, or the mean of
the  latest  bid and  asked  prices  where no last  sales  price  is  available.
Securities traded  over-the-counter are valued at the mean of the latest bid and
asked prices or, in the case of certain foreign securities, at the last reported
sales price,  depending on local  convention or regulation.  Debt securities not
traded on a principal securities exchange are valued through valuations obtained
from a  commercial  pricing  service  or at the mean of the most  recent bid and
asked prices.  When valuations are not readily available,  securities are valued
at fair value as determined in accordance with  procedures  adopted by the Board
of Directors.

     SECURITY  TRANSACTIONS  -- Security  transactions  are accounted for on the
date  purchased or sold.  Net realized  gains and losses are  determined  on the
identified cost basis, which is also used for federal income tax purposes.

     INVESTMENT  INCOME -- Dividend  income less foreign taxes withheld (if any)
is  recorded  as of the  ex-dividend  date.  Interest  income is recorded on the
accrual basis and includes amortization of discounts and premiums.

     FOREIGN  CURRENCY  TRANSACTIONS -- The accounting  records of the Funds are
maintained in U.S. dollars.  All assets and liabilities  initially  expressed in
foreign currencies are converted into U.S. dollars at prevailing exchange rates.
Purchases and sales of investment securities,  dividend and interest income, and
certain  expenses  are  translated  at the rates of exchange  prevailing  on the
respective dates of such transactions.

     Net realized foreign currency  exchange gains or losses arise from sales of
foreign  currencies  and the  difference  between  asset and  liability  amounts
initially stated in foreign  currencies and the U.S. dollar value of the amounts
actually  received or paid. Net unrealized  foreign  currency  exchange gains or
losses  arise from  changes in the value of assets and  liabilities,  other than
portfolio securities, resulting from changes in the exchange rates.

     Net realized  and  unrealized  foreign  currency  exchange  gains or losses
occurring  during the holding period of portfolio  securities are a component of
realized gain (loss) on investments and unrealized  appreciation  (depreciation)
on investments, respectively.

     FORWARD  FOREIGN  CURRENCY  EXCHANGE  CONTRACTS -- The Funds may enter into
forward foreign currency exchange contracts for the purpose of settling specific
purchases or sales of securities  denominated in a foreign  currency or to hedge
the Fund's  exposure  to  foreign  currency  exchange  rate  fluctuations.  When
required,  the Funds will segregate assets in an amount  sufficient to cover its
obligations  under the hedge  contracts.  The net U.S.  dollar  value of foreign
currency  underlying  all  contractual  commitments  held by the  Funds  and the
resulting  unrealized  appreciation or depreciation  are determined  daily using
prevailing exchange rates.  Forward contracts involve elements of risk in excess
of the amount  reflected in the Statement of Assets and  Liabilities.  The Funds
bear the risk of an  unfavorable  change in the foreign  currency  exchange rate
underlying  the  forward  contract.  Additionally,   losses  may  arise  if  the
counterparties do not perform under the contract terms.

     REPURCHASE  AGREEMENTS  -- The Funds may enter into  repurchase  agreements
with institutions the Funds'  investment  manager,  American Century  Investment
Management, Inc. (ACIM), has determined are creditworthy pursuant to

28   Notes to Financial Statements                  American Century Investments


                         NOTES TO FINANCIAL STATEMENTS

APRIL 30, 1997 (UNAUDITED)

criteria  adopted  by the  Board of  Directors.  Each  repurchase  agreement  is
recorded  at cost.  Each  Fund  requires  that  the  securities  purchased  in a
repurchase transaction be transferred to the custodian in a manner sufficient to
enable each Fund to obtain those  securities in the event of a default under the
repurchase  agreement.  ACIM  monitors,  on a  daily  basis,  the  value  of the
securities  transferred to ensure that the value, including accrued interest, of
the  securities  under each  repurchase  agreement  is equal to or greater  than
amounts owed to each Fund under each repurchase agreement.

     JOINT  TRADING  ACCOUNT -- Pursuant  to an  Exemptive  Order  issued by the
Securities  and  Exchange  Commission,  each Fund,  along with other  registered
investment   companies  having  management   agreements  with  ACIM  and  Benham
Management  Corporation,  may transfer  uninvested  cash  balances  into a joint
trading  account.  These  balances  are  invested  in  one  or  more  repurchase
agreements that are collateralized by U.S. Treasury or Agency obligations.

     INCOME  TAX  STATUS  -- It is the  policy of the  Funds to  distribute  all
taxable income and capital gains to shareholders  and to otherwise  qualify as a
regulated  investment  company under  provisions  of the Internal  Revenue Code.
Accordingly, no provision has been made for federal income taxes.

     DISTRIBUTIONS TO SHAREHOLDERS -- Distributions to shareholders are recorded
on the  ex-dividend  date.  Distributions  from net  investment  income  and net
realized gains are declared and paid annually.

     The  character of  distributions  made during the year from net  investment
income or net realized gains may differ from their ultimate characterization for
federal  income tax purposes.  These  differences  are due to differences in the
recognition  of  income  and  expense  items  for  financial  statement  and tax
purposes.

     SUPPLEMENTARY   INFORMATION  --  Certain  officers  and  directors  of  the
Corporation are also officers  and/or  directors,  and, as a group,  controlling
stockholders   of  American   Century   Companies,   Inc.,  the  parent  of  the
Corporation's investment manager, ACIM, the Corporation's distributor,  American
Century Investment Services,  Inc., ACIS, and the Corporation's  transfer agent,
American Century Services Corporation.

     USE OF ESTIMATES -- The  preparation of financial  statements in conformity
with  generally  accepted  accounting  principles  requires  management  to make
estimates  and  assumptions  that  affect  the  reported  amounts  of assets and
liabilities  and disclosure of contingent  assets and liabilities at the date of
the financial statements, and the reported amounts of increases and decreases in
net assets from  operations  during the reporting  period.  Actual results could
differ from those estimates.

- -----------------------------------------------------------------------------
2. TRANSACTIONS WITH RELATED PARTIES

     The  Corporation  has entered  into a Management  Agreement  with ACIM that
provides the Funds with investment  advisory and management services in exchange
for a single,  unified  management fee per class.  Additional  fees apply to the
Advisor Class, as described in the respective prospectus. The Agreement provides
that all expenses of the Funds, except brokerage  commissions,  taxes, interest,
expenses  of those  directors  who are not  considered  "interested  persons" as
defined in the  Investment  Company  Act of 1940  (including  counsel  fees) and
extraordinary expenses, will be paid by ACIM. The fee is computed daily and paid
monthly  based on each  Fund's  average  daily  closing  net  assets  during the
previous month. The annual  management fee for each class is 1.00% and 0.80% for
the Investor Class and Institutional Class, respectively.

     The Board of Directors has adopted a shareholder  services and distribution
plan for the Advisor Class, pursuant to Rule 12b-1 of the Investment Company Act
of 1940. The Advisor Class Master  Distribution  and  Shareholder  Services Plan
provides that the Funds will pay ACIM an annual  distribution fee equal to 0.25%
and service fee equal to 0.25%.  The fees are  computed  daily and paid  monthly
based on the  Advisor  Class's  average  daily  closing  net  assets  during the
previous month.  The  distribution  fee provides  compensation  for distribution
expenses  incurred in connection with  distribution  shares of the Advisor Class
including,  but not limited to,  payments to  brokers,  dealers,  and  financial
institutions  that have entered into sales agreements with ACIS and/or ACIM. The
service fee provides  compensation for shareholder and  administrative  services
rendered by ACIM, its affiliates or independent third party providers.

Semiannual Report                           Notes to Financial Statements     29


                         NOTES TO FINANCIAL STATEMENTS

APRIL 30, 1997 (UNAUDITED)

- --------------------------------------------------------------------------------
3. INVESTMENT TRANSACTIONS

     Investment  transactions  (excluding short-term investments) for the period
ended April 30, 1997 were as follows:

                                     SELECT           HERITAGE          GROWTH

PURCHASES                                         ($ in Thousands)

Common Stocks..................   $2,303,127          $261,233        $1,813,109
Other Debt Obligations.........          --             32,508              --

PROCEEDS FROM SALES

Common Stocks..................   $2,506,201          $343,445        $2,555,456
Preferred Stocks...............       17,183               --               --
Other Debt Obligations.........          --              4,370              --

     On  April  30,  1997,  the  composition  of  unrealized   appreciation  and
(depreciation)  of  investment   securities  based  on  the  aggregate  cost  of
investments for federal income tax purposes was as follows:

                                     SELECT           HERITAGE          GROWTH

                                                  ($ in Thousands)

Appreciation...................   $  865,910          $246,120        $1,010,232
(Depreciation).................     (15,540)          (50,718)          (51,548)
Net............................      850,370           195,402           958,684
Federal Tax Cost...............    3,393,611           870,303         3,451,780

- --------------------------------------------------------------------------------
4. CAPITAL SHARE TRANSACTIONS

     There are 250,000,000,  250,000,000, and 500,000,000 shares of the Investor
Class  authorized for issuance by Select,  Heritage,  and Growth,  respectively.
There are 41,000,000 shares of the  Institutional  Class authorized for issuance
by Select. All shares are $0.01 par value.
Transactions in shares of the Funds were as follows:

<TABLE>
                                                         SELECT                       HERITAGE                        GROWTH

                                                  Shares       Amount            Shares       Amount            Shares      Amount

INVESTOR CLASS                                                                     (In Thousands)

SIX MONTHS ENDED APRIL 30, 1997:
<S>                                                <C>      <C>                  <C>       <C>                  <C>      <C>        
Sold........................................       8,841    $   361,200          15,311    $  189,210           19,893   $   454,016
Issued in reinvestment of distributions.....       9,469        371,412           5,793        68,885            3,935        87,875
Redeemed....................................    (14,906)      (606,276)        (20,354)     (250,731)         (47,398)   (1,070,173)
                                             -----------    -----------     -----------   -----------      -----------   -----------
Net increase (decrease).....................       3,404    $   126,336             750    $    7,364         (23,570)   $ (528,282)
                                             ===========    ===========     ===========   ===========      ===========   ===========
INVESTOR CLASS

YEAR ENDED OCTOBER 31, 1996:
Sold........................................      10,936    $   416,837          22,820    $  266,770           34,900   $   721,179
Issued in reinvestment of distributions.....      13,373        471,136           5,129        56,471           34,403       659,172
Redeemed....................................    (28,464)    (1,078,556)        (25,302)     (295,150)         (69,582)   (1,425,910)
                                             -----------    -----------     -----------   -----------      -----------   -----------
Net increase (decrease).....................     (4,155)    $ (190,583)           2,647    $   28,091            (279)   $  (45,559)
                                             ===========    ===========     ===========   ===========      ===========   ===========
</TABLE>

30   Notes to Financial Statements           American Century Investments


                         NOTES TO FINANCIAL STATEMENTS

APRIL 30, 1997 (UNAUDITED)

- --------------------------------------------------------------------------------
4. CAPITAL SHARE TRANSACTIONS (CONT.)

                                                         SELECT

                                                 Shares         Amount

INSTITUTIONAL CLASS                                  (In Thousands)

MARCH 14, 1997(1) THROUGH APRIL 30, 1997:

Sold........................................        255         $10,340
                                               --------        --------
Net increase................................        255         $10,340
                                               ========        ========

(1)  Sale of the  Institutional  Class for Select  commenced  on March 14, 1997.
     Sale of the  Institutional  Class had not commenced for Heritage and Growth
     as of April 30, 1997.

- --------------------------------------------------------------------------------
5. AFFILIATED COMPANY TRANSACTIONS

     A summary of transactions  for each issuer who is or was an affiliate at or
during the six months ended April 30, 1997, follows:
<TABLE>

                                                                                                April 30, 1997
<S>                             <C>          <C>              <C>          <C>              <C>             <C>    
                                  Share                                     Realized
                                 Balance      Purchase         Sales          Gain            Share         Market
Fund/Issuer(1)                  10/31/96        Cost           Cost          (Loss)          Balance         Value

HERITAGE                                                        ($ in Thousands)

Inacom Corp.                       --        $ 16,310            --              --         580,000         $12,724
                                           ==========      ==========     ==========                     ==========
GROWTH

Xylan Corp.                        --        $118,765         $95,886      $(58,870)        650,000         $ 9,750
                                           ==========      ==========     ==========                     ==========

(1)  None of the securities produced income during the period held.
</TABLE>

- -----------------------------------------------------------------------------
6. CORPORATE EVENTS

     The following name changes became effective January 1, 1997:
<TABLE>

                      NEW NAMES                                                   FORMER NAMES

<S>                  <C>                                                        <C> 
FUNDS' ISSUER:        American Century Mutual Funds, Inc.                         Twentieth Century Investors, Inc.
FUNDS:                American Century - Twentieth Century Select Fund            Select Investors
                      American Century - Twentieth Century Heritage Fund          Heritage Investors
                      American Century - Twentieth Century Growth Fund            Growth Investors
PARENT COMPANY:       American Century Companies, Inc.                            Twentieth Century Companies, Inc.
DISTRIBUTOR:          American Century Investment Services, Inc.                  Twentieth Century Securities, Inc.
TRANSFER AGENT:       American Century Services Corporation                       Twentieth Century Services, Inc.
</TABLE>

Semiannual Report                           Notes to Financial Statements     31

<TABLE>
<CAPTION>
                              FINANCIAL HIGHLIGHTS
                                     SELECT

                                               For a Share Outstanding Throughout the Years Ended October 31 (except as noted)

                                                                            Investor                                Institutional
                                                                              Class                                     Class

                                                 1997(1)     1996       1995       1994       1993       1992          1997(2)

PER-SHARE DATA

<S>                                              <C>        <C>        <C>        <C>        <C>        <C>             <C>   
Net Asset Value, Beginning of Period........     $41.52     $39.52     $37.67     $45.76     $39.18     $40.79          $40.79
                                              ---------  ---------  ---------  ---------  ---------  ---------       ---------

Income From Investment Operations

   Net Investment Income....................    0.07(3)    0.20(3)    0.33(3)       0.40       0.46       0.53         0.01(3)

   Net Realized and Unrealized Gain
   (Loss) on Investment Transactions........       4.21       6.73       4.68     (3.59)       7.94       0.34            1.01
                                              ---------  ---------  ---------  ---------  ---------  ---------       ---------
   Total From
   Investment Operations....................       4.28       6.93       5.01     (3.19)       8.40       0.87            1.02
                                              ---------  ---------  ---------  ---------  ---------  ---------       ---------
Distributions

   From Net Investment Income...............     (0.32)     (0.27)     (0.28)     (0.43)     (0.49)     (0.65)              -

   From Net Realized Gains
   on Investment Transactions...............     (3.68)     (4.66)     (2.75)     (4.47)     (1.31)     (1.83)              -

   Distributions in Excess
   of Net Realized Gains....................         -          -      (0.13)         -      (0.02)         -               -
                                              ---------  ---------  ---------  ---------  ---------  ---------       ---------
   Total Distributions......................     (4.00)     (4.93)     (3.16)     (4.90)     (1.82)     (2.48)               -
                                              ---------  ---------  ---------  ---------  ---------  ---------       ---------
Net Asset Value, End of Period..............     $41.80     $41.52     $39.52     $37.67     $45.76     $39.18          $41.81
                                              =========  =========  =========  =========  =========  =========       =========
   Total Return(4)..........................     10.96%     19.76%     15.02%    (7.37)%     22.20%      1.76%           2.50%

RATIOS/SUPPLEMENTAL DATA

Ratio of Operating Expenses
to Average Net Assets.......................   1.00%(5)      1.00%      1.00%      1.00%      1.00%      1.00%        0.80%(5)

Ratio of Net Investment Income to
Average Net Assets..........................   0.35%(5)      0.50%      0.90%      1.00%      1.10%      1.40%        0.05%(5)

Portfolio Turnover Rate.....................        57%       105%       106%       126%        82%        95%             57%

Average Commission Paid per
Investment Security Traded..................    $0.0457    $0.0410    $0.0460       -(6)       -(6)       -(6)         $0.0457

Net Assets, End
of Period (in millions).....................     $4,208     $4,039     $4,008     $4,278     $5,160     $4,534             $11

(1)  Six months ended April 30, 1997 (unaudited).

(2)  March 14, 1997 (commencement of sale of Institutional  Class) through April
     30, 1997 (unaudited).

(3)  Computed using average shares outstanding throughout the period.

(4)  Total  return   assumes   reinvestment   of  dividends  and  capital  gains
     distributions, if any. Total returns for periods less than one year are not
     annualized.

(5)  Annualized.

(6)  Disclosure of average  commission  paid per investment  security traded was
     not required prior to the year ended October 31, 1995.
</TABLE>

See Notes to Financial Statements

32   Financial Highlights                           American Century Investments

<TABLE>
<CAPTION>
                              FINANCIAL HIGHLIGHTS
                                    HERITAGE

                                                For a Share Outstanding Throughout the Years Ended October 31 (except as noted)

                                               1997(1)        1996          1995           1994         1993           1992

PER-SHARE DATA

Net Asset Value,
<S>                                            <C>           <C>            <C>           <C>            <C>            <C>  
Beginning of Period.......................     $12.24        $11.75         $10.32        $11.03         $9.30          $8.59
                                            ---------     ---------      ---------     ---------     ---------      ---------
Income From Investment Operations

   Net Investment Income .................       -(2)          -(2)        0.05(2)          0.07          0.07           0.10

   Net Realized and Unrealized Gain
   (Loss) on Investment Transactions......       0.58          1.15           1.96        (0.21)          2.43           0.72
                                            ---------     ---------      ---------     ---------     ---------      ---------
   Total From
   Investment Operations..................       0.58          1.15           2.01        (0.14)          2.50           0.82
                                            ---------     ---------      ---------     ---------     ---------      ---------
Distributions

   From Net Investment Income.............     (0.09)        (0.05)         (0.03)        (0.06)        (0.09)         (0.11)

   From Net Realized Gains on
   Investment Transactions................     (0.71)        (0.61)         (0.52)        (0.50)        (0.68)            -

   Distributions in Excess of

   Net Realized Gains.....................         -             -          (0.03)        (0.01)            -             -
                                            ---------     ---------      ---------     ---------     ---------      ---------
   Total Distributions....................     (0.80)        (0.66)         (0.58)        (0.57)        (0.77)         (0.11)
                                            ---------     ---------      ---------     ---------     ---------      ---------
Net Asset Value, End of Period............     $12.02        $12.24         $11.75        $10.32        $11.03          $9.30
                                            =========     =========      =========     =========     =========      =========
   Total Return(3)........................      4.80%        10.44%         21.04%       (1.13)%        28.64%          9.65%

RATIOS/SUPPLEMENTAL DATA

Ratio of Operating Expenses
to Average Net Assets.....................   1.00%(4)         0.99%          0.99%         1.00%         1.00%          1.00%

Ratio of Net Investment Income
to Average Net Assets.....................          -             -          0.50%         0.70%         0.70%          1.10%

Portfolio Turnover Rate...................        27%          122%           121%          136%          116%           119%

Average Commission Paid per
Investment Security Traded................    $0.0464       $0.0420        $0.0420          -(5)          -(5)           -(5)

Net Assets, End
of Period (in millions)...................     $1,072        $1,083         $1,008          $897          $702           $369

(1)  Six months ended April 30, 1997 (unaudited).

(2)  Computed using average shares outstanding throughout the period.

(3)  Total  return   assumes   reinvestment   of  dividends  and  capital  gains
     distributions, if any. Total returns for periods less than one year are not
     annualized.

(4)  Annualized.

(5)  Disclosure of average  commission  paid per investment  security traded was
     not required prior to the year ended October 31, 1995.
</TABLE>

See Notes to Financial Statements

Semiannual Report                                    Financial Highlights     33


<TABLE>
<CAPTION>
                              FINANCIAL HIGHLIGHTS
                                     GROWTH

                                                For a Share Outstanding Throughout the Years Ended October 31 (except as noted)

                                               1997(1)        1996          1995           1994         1993           1992

PER-SHARE DATA

Net Asset Value,
<S>                                            <C>           <C>            <C>           <C>           <C>         <C>   
Beginning of Period.......................     $22.21        $23.88         $22.99        $25.27        $23.64      $22.32
                                            ---------     ---------      ---------     ---------     ---------   ---------
Income From Investment Operations

     Net Investment Income (Loss).........    0.02(2)     (0.01)(2)        0.08(2)          0.06          0.06      (0.02)

     Net Realized and Unrealized Gain
     on Investment Transactions...........       1.11          1.47           4.08          0.48          1.94        1.35
                                            ---------     ---------      ---------     ---------     ---------   ---------
     Total From

     Investment Operations................       1.13          1.46           4.16          0.54          2.00        1.33
                                            ---------     ---------      ---------     ---------     ---------   ---------
Distributions

     From Net Investment Income...........     (0.18)        (0.07)         (0.05)        (0.06)            -       (0.01)

     From Net Realized Gains on
     Investment Transactions..............     (0.25)        (2.98)         (3.18)        (2.76)        (0.36)          -

     Distributions in Excess of
     Net Realized Gains...................         -         (0.08)         (0.04)            -         (0.01)          -
                                            ---------     ---------      ---------     ---------     ---------   ---------
     Total Distributions..................     (0.43)        (3.13)         (3.27)        (2.82)        (0.37)      (0.01)
                                            ---------     ---------      ---------     ---------     ---------   ---------
Net Asset Value, End of Period............     $22.91        $22.21         $23.88        $22.99        $25.27      $23.64
                                            =========     =========      =========     =========     =========   =========
     Total Return(3)......................      5.13%         8.18%         22.31%         2.66%         8.48%       5.96%

RATIOS/SUPPLEMENTAL DATA

Ratio of Operating Expenses
to Average Net Assets.....................   1.00%(4)         1.00%          1.00%         1.00%         1.00%       1.00%

Ratio of Net Investment Income (Loss)
to Average Net Assets.....................   0.08%(4)       (0.10)%          0.40%         0.30%         0.20%     (0.10)%

Portfolio Turnover Rate...................        41%          122%           141%          100%           94%         53%

Average Commission Paid per
Investment Security Traded................    $0.0380       $0.0360        $0.0400          -(5)          -(5)        -(5)

Net Assets, End
of Period (in millions)...................     $4,375        $4,765         $5,130        $4,363        $4,641      $4,472

(1)  Six months ended April 30, 1997 (unaudited).

(2)  Computed using average shares outstanding throughout the period.

(3)  Total  return   assumes   reinvestment   of  dividends  and  capital  gains
     distributions, if any. Total returns for periods less than one year are not
     annualized.

(4)  Annualized.

(5)  Disclosure of average  commission  paid per investment  security traded was
     not required prior to the year ended October 31, 1995.
</TABLE>

See Notes to Financial Statements

34   Financial Highlights                           American Century Investments


                                SHARE CLASS AND
                         RETIREMENT ACCOUNT INFORMATION

SHARE CLASSES

     Until  September 3, 1996, the Select,  Heritage and Growth funds issued one
class of fund shares,  reflecting the fact that most investors in the funds were
individuals  investing  on their  own  behalf.  To serve  the  diverse  needs of
American Century's investors,  additional classes of shares are now available in
Select, Heritage and Growth.

     The original class of Select, Heritage and Growth fund shares is called the
INVESTOR CLASS. All shares issued and outstanding before September 3, 1996, have
been  designated as Investor  Class shares.  Investor  Class shares may still be
purchased  after September 3, 1996.  Investor Class  shareholders do not pay any
commissions  or other fees for purchase of fund shares  directly  from  American
Century.  Investors who buy Investor Class shares through a broker-dealer may be
required to pay the  broker-dealer a transaction  fee. THE PRICE AND PERFORMANCE
OF THE  INVESTOR  CLASS  SHARES  ARE  LISTED IN  NEWSPAPERS.  NO OTHER  CLASS IS
CURRENTLY LISTED.

     In  addition,  there  is an  INSTITUTIONAL  CLASS,  which is  available  to
endowments,   foundations,   defined   benefit   pension   plans  or   financial
intermediaries  serving these  investors.  This class of shares  recognizes  the
relatively lower cost of serving  institutional  customers and others who invest
at least $5  million  in an  American  Century  fund or at least $10  million in
multiple funds. In recognition of the larger investments and comparatively lower
transaction costs, the total expense ratio of the Institutional  Class shares is
0.20% less than the total expense ratio of the Investor  Class.  As of April 30,
1997, American Century had begun selling these shares in Select but not Heritage
and Growth.

     There  is  also  an   ADVISOR   CLASS,   which  is  sold   through   banks,
broker-dealers,  insurance  companies and financial  advisors.  The sale of this
class had not commenced as of April 30, 1997. All classes of shares  represent a
pro  rata  interest  in the  funds  and  generally  have  the  same  rights  and
preferences.

RETIREMENT ACCOUNT INFORMATION

     As required by law, any  distributions  you receive from an IRA and certain
403(b)  distributions [not eligible for rollover to an IRA or to another 403(b)]
are subject to federal  income tax  withholding  at the rate of 10% of the total
amount withdrawn,  unless you elect not to have withholding  apply. If you don't
want us to withhold on this amount, you may send us a written notice not to have
the federal  income tax  withheld.  Your written  notice is valid for six months
from the date of receipt at American Century.  Even if you plan to roll over the
amount you withdraw to another tax-deferred  account, the withholding rate still
applies to the withdrawn  amount unless we have received a written notice not to
withhold federal income tax within six months prior to the withdrawal.

     When you plan to withdraw,  you may make your  election by  completing  our
Exchange/  Redemption form or an IRS Form W-4P. Call American Century for either
form.  Your  written  election  is valid  for only six  months  from the date of
receipt at American Century. You may revoke your election at any time by sending
a written notice to us.

     Remember, even if you elect not to have income tax withheld, you are liable
for paying income tax on the taxable  portion of your  withdrawal.  If you elect
not to have income tax  withheld or you don't have enough  income tax  withheld,
you may be  responsible  for payment of estimated  tax. You may incur  penalties
under the estimated tax rules if your withholding and estimated tax payments are
not sufficient.

Semiannual Report          Share Class and Retirement Account Information     35


                             BACKGROUND INFORMATION

INVESTMENT PHILOSOPHY AND POLICIES

     The  Twentieth  Century  Group  offers nine equity funds that invest in the
stocks  of  growing  companies,  both  domestically  and  internationally.   The
philosophy  behind  these growth funds  focuses on three  important  principles.
First, the funds seek to own successful companies, which we define as those with
growing  earnings  and  revenues.  Second,  we attempt  to keep the funds  fully
invested,  regardless of short-term  market activity.  Experience has shown that
market  gains  can  occur  in  unpredictable   spurts  and  that  missing  those
opportunities can  significantly  limit potential for gain. Third, the funds are
managed by teams,  rather than by one "star." We believe  this allows us to make
better, more consistent management decisions.

     In addition to these principles, each fund has its own investment policies:

     TWENTIETH  CENTURY  SELECT seeks  large,  established  companies  that show
accelerating  growth  rates;  also,  at least 80% of the fund's  assets  must be
invested in stocks or securities that pay regular dividends or otherwise produce
income.  These dividends,  and the established  nature of the companies in which
Select invests, help lessen the fund's short-term price fluctuations.

     TWENTIETH  CENTURY  HERITAGE  seeks  smaller and  mid-sized  firms  showing
accelerating  growth rates,  and at least 80% of its assets must be in stocks or
securities  paying  regular  dividends  or  otherwise  producing  income.  While
Heritage's  dividend  requirement  should make the fund less volatile than funds
without dividends, it should also display somewhat more price variability -- and
greater long-term growth potential -- than Select.

     TWENTIETH  CENTURY GROWTH invests in larger,  more  established  firms that
exhibit  accelerating  growth.  Because the value of established  firms tends to
change  relatively  slowly,  Growth  can  ordinarily  be  expected  to show more
moderate  price  fluctuations  than the growth  funds that  invest in smaller or
mid-sized firms.

COMPARATIVE INDICES

     The following  indices are used in the report to serve as fund  performance
comparisons. They are not investment products available for purchase.

     The S&P 500 is a  capitalization-weighted  index of the  stocks  of the 500
largest publicly traded companies.  Created by Standard & Poor's Corporation, it
is considered to be a broad measure of U.S. stock market performance.

     The S&P MIDCAP 400 INDEX is a  capitalization-weighted  index of the stocks
of the 400 largest  publicly traded U.S.  companies not included in the S&P 500.
Created by Standard & Poor's  Corporation,  it is  considered  to represent  the
performance of  mid-capitalization  stocks  generally.  The index was created in
March 1994. Data presented for prior periods have been provided by S&P.

                  FUND MANAGEMENT TEAM LEADERS

                  SELECT:
                  Portfolio Manager         Jean Ledford
                  Portfolio Manager         Chuck Duboc

                  HERITAGE:
                  Portfolio Manager         Nancy Prial
                  Portfolio Manager         Kevin Lewis

                  GROWTH:
                  Portfolio Manager         James Stowers III

36   Background Information                         American Century Investments


                                    GLOSSARY

RETURNS

o TOTAL  RETURN  figures  show the overall  percentage  change in the value of a
hypothetical  investment  in  the  fund  and  assume  that  all  of  the  fund's
distributions are reinvested.

o AVERAGE ANNUAL RETURNS  illustrate the annually  compounded returns that would
have produced the fund's cumulative total returns if the fund's  performance had
been  constant  over the  entire  period.  Average  annual  returns  smooth  out
variations  in a fund's  return;  they are not the same as  fiscal  year-by-year
results.  For fiscal year-by-year total returns,  please refer to the "Financial
Highlights" on pages 32-34.

PORTFOLIO STATISTICS

o NUMBER OF COMPANIES -- the number of different  companies  held by a fund on a
given date.

o PRICE/EARNINGS (P/E) RATIO -- a stock value measurement calculated by dividing
a company's stock price by its earnings per share,  with the result expressed as
a multiple  instead of as a  percentage.  (Earnings  per share is  calculated by
dividing the after-tax earnings of a corporation by its outstanding shares.)

o PORTFOLIO TURNOVER -- the percentage of a fund's investment  portfolio that is
replaced during a given time period, usually a year. Actively managed portfolios
tend to have higher  turnover than passively  managed  portfolios  such as index
funds.

o EXPENSE RATIO -- the operating expenses of the fund, expressed as a percentage
of average net assets.  Shareholders pay an annual fee to the investment manager
for  investment  advisory  and  management  services.  The expenses and fees are
deducted from fund income, not from each shareholder account. (See Note 2 in the
Notes to Financial Statements.)

TYPES OF STOCKS

o  BLUE-CHIP  STOCKS -- stocks of the most  established  companies  in  American
industry.   They  are  generally  large,   fairly  stable  companies  that  have
demonstrated  consistent  earnings and usually have long-term growth  potential.
Examples include General Electric and Coca-Cola.

o CYCLICAL STOCKS -- generally  considered to be stocks whose price and earnings
fluctuations  tend to follow the ups and downs of the business  cycle.  Examples
include the stocks of  automobile  manufacturers,  steel  producers  and textile
operators.

o GROWTH  STOCKS --  stocks of  companies  that have  experienced  above-average
earnings  growth and appear likely to continue  such growth.  These stocks often
sell at high P/E ratios.  Examples can include the stocks of  high-tech,  health
care and consumer staple companies.

o LARGE-CAPITALIZATION ("LARGE-CAP") STOCKS -- generally considered to be stocks
of  companies  with a market  capitalization  (the  total  value of a  company's
outstanding  stock) of more than $5  billion.  These tend to be the stocks  that
make up the Dow Jones Industrial Average and the S&P 500.

o MEDIUM-CAPITALIZATION  ("MID-CAP") STOCKS -- generally considered to be stocks
of  companies  with a market  capitalization  (the  total  value of a  company's
outstanding  stock) of between $1 billion and $5  billion.  These tend to be the
stocks that make up the S&P 400.

o SMALL-CAPITALIZATION ("SMALL-CAP") STOCKS -- generally considered to be stocks
of  companies  with a market  capitalization  (the  total  value of a  company's
outstanding  stock) of less than $1  billion.  These tend to be the stocks  that
make up the Russell 2000 Index.

o VALUE STOCKS -- generally  considered to be stocks that are purchased  because
they are relatively inexpensive. These stocks are typically characterized by low
P/E ratios.

STATISTICAL TERMINOLOGY

o  PRICE/BOOK  RATIO -- a stock  value  measurement  calculated  by  dividing  a
company's stock price by its book value per share,  with the result expressed as
a multiple  instead of as a  percentage.  (Book value per share is calculated by
subtracting a company's liabilities from its assets, then dividing that value by
the number of outstanding shares.)

Semiannual Report                                                Glossary     37


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Investor Services:
1-800-345-2021 or 816-531-5575

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AMERICAN CENTURY MUTUAL FUNDS, INC.

Investment Manager
AMERICAN CENTURY INVESTMENT MANAGEMENT, INC.
Kansas City, Missouri

This report and the financial  statements contained herein are submitted for the
general  information  of our  shareholders.  The  report is not  authorized  for
distribution  to  prospective  investors  unless  preceded or  accompanied by an
effective prospectus.

American Century Investment Services, Inc.

9706           [recycled logo]
SH-BKT-8632       Recycled
<PAGE>
                                SEMIANNUAL REPORT

                             [american century logo]
                                    American
                                   Century(sm)

                                 APRIL 30, 1997

                                    TWENTIETH
                                     CENTURY
                                      GROUP

                                NEW OPPORTUNITIES


[front cover]



                              TABLE OF CONTENTS

Report Highlights........................................................   1
Our Message to You.......................................................   2
Period Overview..........................................................   3
Performance & Portfolio Information......................................   4
Management Q & A.........................................................   5
Schedule of Investments..................................................   8
Statement of Assets & Liabilities........................................  10
Statement of Operations..................................................  11
Statement of Changes in Net Assets.......................................  12
Notes to Financial Statements............................................  13
Financial Highlights.....................................................  15
Retirement Account Information...........................................  16
Background Information
     Investment Philosophy and Policies..................................  20
     Comparative Indices.................................................  20
     Fund Management Team Leaders........................................  20
Glossary.................................................................  21

     American  Century  Investments  offers you nearly 70 fund choices  covering
stocks, bonds, money markets,  specialty investments and blended portfolios.  To
help you find the  funds  that may meet your  needs,  we have  divided  American
Century funds into three groups based on investment style and objectives.  These
groups, which appear below, are designed to help simplify your fund decisions.

                  American Century Investments--Family of Funds

     Benham Group          American Century Group        Twentieth Century Group

  MONEY MARKET FUNDS         ASSET ALLOCATION &               GROWTH FUNDS
 GOVERNMENT BOND FUNDS         BALANCED FUNDS              INTERNATIONAL FUNDS
DIVERSIFIED BOND FUNDS    CONSERVATIVE EQUITY FUNDS
 MUNICIPAL BOND FUNDS          SPECIALTY FUNDS
                                                            New Opportunities

We welcome your comments or questions about this report.  
See the back cover for ways to contact us by mail, phone or e-mail.

Twentieth  Century and the Benham Group are registered marks of American Century
Services Corporation and Benham Management Corporation,  respectively.  American
Century is a service mark of American Century Services Corporation.


                                                    American Century Investments


                              REPORT HIGHLIGHTS

PERIOD OVERVIEW

o    The U.S. stock market  produced widely  divergent  returns over the period.
     The S&P 500's 14.74% six-month total return continued a three-year trend of
     unusually  strong  performance by large-cap  stocks.  By contrast,  the S&P
     MidCap 400 posted a 6.88% return,  and the small-cap  Russell 2000 returned
     just 1.61%.

o    Factors that were in the S&P 500's favor included: equity investors seeking
     stability and liquidity; strong economic growth with low inflation; and the
     success of S&P 500 index funds.

o    The fast-growing  companies  targeted by New  Opportunities  didn't benefit
     from the factors that drove  investors to the S&P 500. They lagged  despite
     reporting  strong  earnings  growth  in most  cases.  Many  companies  that
     experienced share price declines during the period continued to show strong
     fundamentals.

o    While the S&P 500 and its component  companies were considered a relatively
     safe haven  during the period,  many  investors  viewed mid- and  small-cap
     growth companies as too volatile and unpredictable.  Valuations declined as
     the market priced these stocks by weighting  current  earnings more heavily
     than projected future earnings.


NEW OPPORTUNITIES

o    New Opportunities had a rocky start,  declining 20.00% since its inception.
     The negative performance resulted from the decline of  small-capitalization
     (small-cap)  growth  companies,  compounded by the fund's focus on the most
     rapidly growing stocks within this universe.

o    The companies New  Opportunities  owns continue to report dynamic growth in
     their  revenues and earnings.  This growth,  combined  with the  attractive
     valuation of small-cap  stocks  relative to large-cap  shares,  has put the
     fund in a position to benefit from a small-cap rebound.

o    The  management  team  reduced  holdings in software  providers  because of
     increasing  competition in that industry.  In addition,  the team increased
     holdings in a small group of elite  manufacturers  of specialized  computer
     chips.

o    For the past two years the largest stocks in the S&P 500 index have
     seemingly offered everything an investor could desire; strong earnings
     growth, above average returns, low volatility and superior liquidity. To
     some extent the extraordinary returns have also been self-perpetuating,
     as momentum-following market participants have sold their underperforming
     stocks (often small-cap) to buy the large-cap leaders. New Opportunities'
     management team believes a change in market leadership will probably
     begin with a deteriorating outlook for corporate earnings in general.
     That change may not be too far away.


                NEW OPPORTUNITIES

TOTAL RETURNS:                 AS OF 4/30/97
     Since Inception              -20.00%(1)

NET ASSETS:                     $148 million
     (AS of 4/30/97)

INCEPTION DATE:                     12/26/96

TICKER SYMBOL:                         TWNOX

(1)  Not annualized.

Many of the investment  terms in this report are defined in the Glossary on page
21.


Semiannual Report                                        Report Highlights     1


                             OUR MESSAGE TO YOU

             [photo James E. Stowers, Jr. and James E. Stowers III]

     Twentieth Century New Opportunities Fund was launched on December 26, 1996,
as part of our  commitment  to  offer  additional  funds  and  services  for our
Priority  Investors.  We wish  there  were  better  results to talk about on the
occasion of the fund's first report to share-holders.  Unfortunately, the fund's
early months of operation  coin-cided  with an extremely  difficult stock market
environment for small, rapidly growing companies.

     You may recall that New  Opportunities  takes a very aggressive  investment
stance.  It seeks smaller  companies with strong  earnings  trends and favorable
expectations.  Historically,  this form of investing has been both rewarding and
very  volatile,  and it demands that  investors be willing to accept  short-term
risk on the way to long-term results.

     As  with  our  other  aggressive  equity  funds,  we  strive  to  keep  New
Opportunities  fully  invested in stocks.  As early results show,  this approach
doesn't  provide much cushion when our investment  style is out of favor. On the
other hand, we are always in position to take full  advantage of market  surges,
which can be swift, powerful and unanticipated.

     A significant  portion of New Opportunities'  assets represent  investments
from American Century employees.  We ourselves have personal stakes in the fund,
so we're also affected by down periods.  We know from experience,  though,  that
one of the  worst  things  an  investor  can do is  abandon  a proven  long-term
investment  approach  to chase  whatever  style  might be  working  at the time.
Aggressive  equity  investing takes patience and  discipline.  We have plenty of
both, and are confident that New  Opportunities  will meet its goal of providing
you with solid results over time.


Sincerely,

/s/James E. Stowers, Jr.                   /s/James E. Stowers III
James E. Stowers, Jr.                      James E. Stowers III                 
Chairman of the Board and Founder          President and Chief Executive Officer
                                             




2    Our Message to You                          American Century Investments


                               PERIOD OVERVIEW

WIDELY DIVERGENT RETURNS

     The  six-month  period  ended April 30,  1997,  produced  widely  divergent
returns for U.S.  stock  investors.  In general,  the shares of large  companies
(large-cap stocks),  particularly  relatively stable,  industry-leading firms in
the S&P 500,  significantly  outperformed the shares of faster-growing,  smaller
companies  (mid- and small-cap  stocks).  Value stocks (shares of companies that
are  lower-priced)  generally  out-performed  growth  stocks (those of companies
demonstrating  above-average  earnings  growth)  as  investors  placed  a higher
premium on earnings stability than on earnings growth.

STRONG RETURNS FOR THE S&P 500

     The S&P 500 typically  represents  the large-cap  sector of the U.S.  stock
market.  Many investors  also use the index as a proxy for the U.S.  market as a
whole.  The sustained  advance of the S&P 500 was one of the key success stories
of the period.  The index posted a 14.74%  total  return  during the six months,
continuing  a  three-year  trend  of  unusually  strong  results.  Factors  that
supported the S&P 500's performance included:

o    Investors  seeking  predictable  earnings and liquidity because they feared
     rising  interest  rates  and an  economic  slowdown.  The  shares of large,
     well-known   firms  such  as  Johnson  &  Johnson  and  MicroSoft   rallied
     appreciably.

o    Favorable  economic  conditions  (robust  growth  and  low  inflation)  and
     particularly strong earnings growth for large-cap companies.

o    The  popularity  and  success of S&P 500 index  funds.  With more  investor
     dollars chasing stocks in the S&P 500, the prices of those shares rose much
     faster than the prices of mid- and small-cap stocks.

LOWER RETURNS FOR SMALLER-CAP STOCKS

     Many  analysts  use the S&P 400 MidCap  Index and the Russell 2000 Index to
represent mid- and small-cap stocks, respectively.  As shown in the accompanying
graph, the S&P 500 significantly outperformed the smaller cap indices.

     While the S&P 500 and its component  companies were considered a relatively
safe haven during the period,  many investors  viewed mid- and small-cap  growth
companies as too volatile and unpredictable.  Valuations for the stocks of these
companies  declined as the market priced mid- and  small-cap  growth stocks more
conservatively,  weighting  current  earnings more heavily than projected future
earnings.  Investors also became less willing to pay a premium for  fast-growing
technology and healthcare shares.

     The  resulting  share price  declines were  generally  based more on market
perception than on changes in actual fundamental indicators such as earnings and
revenue.  Many companies  experienced  lower share prices despite  continuing to
show strong operating results.  Defensive-minded analysts questioned whether the
earnings and revenue  projections  for small  companies  would be realized,  and
investors refused to pay the higher prices these shares have been awarded in the
past.

[line graph - data below]

U.S. STOCK MARKET PERFORMANCE (Growth of $1.00)
For the six monthes ended April 30, 1997
- --------------------------------------------------------
DATE     S&P 500           S&P 400          RUSSELL 2000

10/31/96 $1.00             $1.00            $1.00
11/30/96 $1.07             $1.06            $1.04
12/31/96 $1.06             $1.06            $1.07
1/31/97  $1.12             $1.10            $1.09
2/28/97  $1.13             $1.09            $1.06
3/31/97  $1.08             $1.04            $1.01
4/30/97  $1.15             $1.07            $1.02

S&P 500..............14.74%
S&P MidCap 400 ...... 6.88%
Russell 2000..........1.61%
Source: Lipper Analytical Services, Inc.


Semiannual Report                                       Period Overview     3


                     PERFORMANCE & PORTFOLIO INFORMATION

                                                              LIFE OF FUND(1)

TOTAL RETURNS AS OF APRIL 30,1997

New Opportunities............................................      -20.00%(2)
Russell 2000 Growth Index.....................................  -11.59%(2)(3)


(1)  Inception was December 26, 1996.
(2)  Not annualized.
(3)  Return since 12/31/96, the date nearest the fund's inception for which data
     are available.

See pages 20 and 21 for more information about the Russell 2000 Growth Index and
returns.


PORTFOLIO AT A GLANCE
                                          4/30/97
Number of Companies                            68
Median Price/Earnings Ratio                  27.9
Portfolio Turnover                            40%
Expense Ratio                            1.50%(1)

(1) Annualized.


[line graph - data below]

GROWTH OF $10,000 OVER THE LIFE OF THE FUND

Value on 4/30/97
Russell 2000 Growth        $8,841
New Opportunities $7,859

          New              Russell 2000
     Opportunities            Growth
        $10,000               $10,000
        $9,745                $10,242
        $8,762                $9,623
        $7,957                $8,944
        $7,859                $8,844


Past  performance  does not  guarantee  future  results.  Investment  return and
principal  value will fluctuate,  and redemption  value may be more or less than
original cost.

The  line  representing  New  Opportunities'  total  return  includes  operating
expenses (such as transaction  costs and management  fees) that reduce  returns,
while the total return line of the Russell 2000 Growth Index does not.


 4   Performance & Portfolio Information          American Century Investments


                               MANAGEMENT Q&A

     An interview with Glenn Fogle and John Seitzer,  portfolio  managers on the
New Opportunities management team.

HOW DID THE FUND PERFORM FROM ITS INCEPTION UNTIL APRIL 30?

     New  Opportunities  suffered  a rocky  start,  declining  20.00%  since its
inception.  The  fund's  negative  performance  resulted  from  the  decline  in
small-capitalization  (small-cap) growth stocks,  compounded by our focus on the
most rapidly  growing  companies  within this sector of the equity  market.  Our
concentration on these businesses,  hardest hit by negative investor  sentiment,
caused the fund to suffer a greater decline than benchmark market indices.

     When reflecting on New Opportunities'  performance during its early months,
it is  important  to keep in mind  that we  manage  the  fund  aggressively  for
long-term  returns.  As a  result,  the  fund  can be very  volatile,  sometimes
significantly  underperforming  the  market  and at  other  times  significantly
outperforming it.

     Our  management  of  the  fund  has  been  consistent  with  our  long-held
aggressive growth investment discipline. We bought and now own some great growth
companies.  Unfortunately,  as  sometimes  happens,  the prices of many of those
stocks have fallen since we acquired them, in spite of strong earnings  reports.
We are prepared to retain the shares of good businesses that meet our investment
standards even if they fall  temporarily out of favor and their share prices lag
for a while.  While the past is no guarantee of the future, our experience tells
us that over the long-term we should be rewarded with higher share prices.

HOW DID SMALL-CAP GROWTH STOCKS PERFORM IN GENERAL?

     The Russell 2000 Growth Index,  which many investment  analysts consider to
be  an  appropriate  proxy  for  small-cap  growth  stock  performance,  is  the
performance  benchmark for the fund. It declined  11.59% during the period.  The
median market  capitalization  of the Russell 2000 Growth Index is approximately
$400 million, which makes it a close match with New Opportunities' median market
capitalization of $345 million.

WHY DID NEW OPPORTUNITIES' PERFORMANCE LAG THAT OF ITS BENCHMARK?

     Unlike an index  fund,  New  Opportunities  makes no  attempt  to match any
benchmark  returns  over  short-term  periods.  In  seeking  superior  long-term
returns,  the fund's  holdings will typically have much higher growth rates than
the Russell  index  average and the fund will usually  appear more  expensive on
absolute  valuation  measures.  Over time,  we expect the  exceptional  earnings
growth  potential of the stocks New  Opportunities  owns to more than offset the
premium we may pay to buy them. In the short term, however, the fund can be very
volatile and markedly underperform the index.

     The  performance  of  technology  stocks  had a large  impact on the fund's
returns.  We built fairly substantial  positions in the shares of companies such
as  Vantive  Corporation,  which  makes  call-tracking  software,  and  Rational
Software,  a provider of software  development tools. Many technology stocks are
appealing to us because  innovation  in these areas  continues to produce  rapid
sales growth and rising profit  margins.  However,  the software field is highly
competitive. A software company's asset base is intellectual property--which can
become less valuable as competitors introduce new products. Given this uncertain
and  fast-changing  environment,  investors  grew  increasingly  concerned  that
earnings were becoming less  predictable,  so many  technology  stocks  declined
despite the earnings  growth they reported.  This flight to larger,  more stable
stocks accounted for a significant portion of the fund's


Semiannual Report                                        Management Q&A     5

                               MANAGEMENT Q&A

underperformance during the period.

CAN YOU GIVE INVESTORS ENCOURAGEMENT ABOUT THE FUND'S PERFORMANCE?

     There are several  factors that encourage us about the long-term  prospects
for New  Opportunities.  The number of new stock  offerings  (IPOs) has declined
dramatically in 1997 compared to the prior two years,  stemming the flood of new
issues that were  crowding the market.  The sell-off in small-cap  growth stocks
has brought their  valuation  relative to large-cap  stocks down to historically
low levels.  Finally,  the  companies  that New  Opportunities  owns continue to
report dynamic growth in their revenues and earnings.

     We've  learned  from years of  experience  that the stock  market  moves in
cycles.  Periods such as the recent one, when uncertainty  about the strength of
the  economy and the  direction  of interest  rates makes stock  investors  more
conservative,  are normal. Our investment  discipline is currently out of favor,
but significant shifts in the small-cap market can be swift. We believe that the
best  strategy for the fund is to stick with our proven style rather than become
defensive  and risk  missing  part of the  market  rebound in these  stocks.  We
believe that eventually market sentiment should shift again, and when it does we
would  expect  these  fast-growing  companies  to  reward  investors  for  their
patience. We continue to believe in the long-term prospects of the fund.

WHAT CHANGES HAVE YOU MADE TO THE PORTFOLIO,  IF ANY,  DURING ITS INITIAL MONTHS
OF OPERATION?

     Our sector  weightings  have not changed  significantly.  However,  we have
shifted our focus somewhat  within those sectors.  For example,  the sell-off in
technology  shares hit industry leaders as well as less  established  companies,
which  enabled us to build  positions  in  companies  showing  stronger  current
earnings  acceleration.  We moved  generally  from  software  providers  such as
Vantive and Rational  Software to manufacturers  such as Jabil Circuit,  Inc., a
contract  manufacturer  of  electronic  components.  We've  also  increased  our
holdings  in a small  group of elite  manufacturers  that  produce  specialized,
high-speed  computer  chips.  These  chips  are made out of a  substance  called
gallium  arsenide,  which  processes  data at faster  speeds  than  conventional
silicon.  Demand for the chips is exploding and only a few suppliers are capable
of manufacturing them.

     In the area of retail  merchandise,  we shifted money from weakening stocks
to those with fresh signs of accelerating  growth.  For example,  we reduced our
position in Finish Line, Inc., an athletic shoe retailer. We were concerned that
Nike,  which  comprises 70% of the company's  revenues,  may see some slowing in
sales  following an  extremely  strong  1996.  We also bought  shares of Pacific
Sunwear,  a mall-based  retailer of casual apparel and accessories for teens and
young adults, based on the stock's accelerating  earnings and revenue growth. We
continue to see opportunities in

TOP TEN HOLDINGS                  % of fund investments
                                                 As of
                                                4/30/97
HBO & Co.                                          3.5%
PAREXEL International Corp.                        3.1%
Wolverine World Wide, Inc.                         3.1%
Action Performance Cos. Inc.                       2.7%
Innovex, Inc.                                      2.6%
McAfee Associates, Inc.                            2.4%
Helen of Troy Ltd.                                 2.3%
Veeco Instruments Inc.                             2.1%
Vitesse Semiconductor Corp.                        2.0%
Applied Magnetics Corp.                            2.0%


TOP FIVE INDUSTRIES               % of fund investments
                                                 As of
                                                 4/3097
Electrical & Electronic
   Components                                      9.1%
Communications Equipment                           8.9%
Computer Software & Services                       8.8%
Consumer Products                                  7.3%
Machinery & Equipment                              7.1%


6    Management Q&A                              American Century Investments


                               MANAGEMENT Q&A

retail apparel, and believe we are well-positioned going forward.

WHAT IS YOUR OUTLOOK FOR SMALL-CAPITALIZATION STOCKS?

     The  outperformance  of large-cap  stocks over the past year has  coincided
with a period of better-than-average (and better-than-expected) earnings growth,
which we think is attributable to the surprisingly robust economy.  For the past
two  years  the  largest  stocks in the S&P 500  index  have  seemingly  offered
everything  an investor  could desire:  strong  earnings  growth,  above average
returns,   low  volatility  and  superior   liquidity.   To  some  extent,   the
extraordinary  returns have also been  self-perpetuating,  as momentum-following
market participants have sold their underperforming  stocks (often small-cap) in
order to buy the large-cap leaders.

     We think  that a change in market  leadership  will  probably  begin with a
deteriorating outlook for earnings, and that change may not be too far away. The
pace of  economic  growth  in the first  months  of 1997  does not  appear to be
sustainable,  and the Federal  Reserve seems intent on ensuring that the economy
cools down.  Slower  growth,  higher  interest rates and a strong dollar all put
pressure on the earnings growth rates of larger  companies.  With profit margins
at many of the large-cap companies already at historically high levels, it seems
probable  that  their  earnings  growth  rates  will  decline  over the next few
quarters.  Some smaller companies will suffer the same deterioration,  but those
that  can  buck  the  trend  should  attract  growth-oriented   investors.   The
inexpensive  relative  valuation of small-cap  stocks should also  contribute to
their recovery.

     The year-long  divergence  between  small-cap and large-cap  stocks is very
unusual,   which  suggests  the  strong  possibility  of  a  small-cap  rebound.
Unfortunately,  there is no telling  precisely when this might happen or to what
degree.  We avoid trying to time the market (and we  discourage  fund  investors
from doing so) because market trends can reverse  abruptly and without  warning.
Instead,  we concentrate on keeping the fund well positioned with investments in
healthy,  growing businesses with the strongest fundamental outlook we can find.
We don't have any control over the timing of how the market  reacts,  but we can
control our investment strategy and implementation. We appreciate our investors'
patience and ongoing trust in us.

EDITOR'S NOTE ON JUNE 6, 1997:

     SINCE APRIL 30, NEW OPPORTUNITIES' SHARE VALUE HAS RISEN BY 21.5%, COMPARED
TO AN INCREASE OF 7.1% IN THE S&P 500. THE CHANGE IN MARKET SENTIMENT  REGARDING
SMALL COMPANIES MAY HAVE BEGUN.


Semiannual Report                                        Management Q&A     7


                           SCHEDULE OF INVESTMENTS

APRIL 30, 1997 (UNAUDITED)

Shares                         ($ in Thousands)                         Value
- -----------------------------------------------------------------------------

COMMON STOCKS

AEROSPACE & DEFENSE--1.8%
      107,300     Triumph Group, Inc.(1)                           $   2,723
                                                                   ----------

AGRICULTURE--1.1%
      142,000     Northland Cranberries, Inc.                          1,651
                                                                   ----------

AUTOMOBILES & AUTO PARTS--2.0%
       80,000     Tower Automotive, Inc.(1)                            2,960
                                                                   ----------

BIOTECHNOLOGY--4.5%
       22,700     Agouron Pharmaceuticals, Inc.(1)                     1,454
       62,800     Centocor, Inc.(1)                                    1,770
       59,000     PathoGenesis Corp.(1)                                1,541
       46,700     Sangstat Medical Corp.(1)                              806
       37,000     Vertex Pharmaceuticals, Inc.(1)                      1,170
                                                                   ----------
                                                                       6,741
                                                                   ----------

BUSINESS SERVICES & SUPPLIES--3.7%
       41,000     Administaff, Inc.(1)                                   764
       20,000     IBAH, Inc.(1)                                           90
      167,000     PAREXEL International Corp.(1)                       4,686
                                                                   ----------
                                                                       5,540
                                                                   ----------

COMMUNICATIONS EQUIPMENT--8.9%
       72,600     Boston Technology, Inc.(1)                           1,452
      100,375     Brightpoint, Inc.(1)                                 2,196
       81,000     Coherent Communications
                     Systems Corp.(1)                                  1,347
       40,000     Davox Corp.(1)                                       1,340
      113,100     Natural MicroSystems Corp.(1)                        2,375
      119,800     REMEC, Inc.(1)                                       2,680
       87,000     Teledata Communications(1)                           1,930
                                                                   ----------
                                                                      13,320
                                                                   ----------

 COMPUTER PERIPHERALS--5.1%
       65,000     AccelGraphics, Inc.(1)                                 691
      118,400     Applied Magnetics Corp.(1)                           2,975
      123,000     Innovex, Inc.                                        3,913
                                                                   ----------
                                                                       7,579
                                                                   ----------


Shares                   ($ in Thousands)                               Value
- -----------------------------------------------------------------------------

COMPUTER SOFTWARE & SERVICES--8.8%
       98,000     HBO & Co.                                      $     5,237
      119,900     HCIA(1)                                              2,495
       75,000     JDA Software Group, Inc.(1)                          1,927
       63,000     McAfee Associates, Inc.(1)                           3,512
                                                                   ----------
                                                                      13,171
                                                                   ----------
CONSUMER PRODUCTS--7.3%
      149,000     Helen of Troy Ltd.(1)                                3,492
      152,700     NBTY, Inc.(1)                                        2,873
      113,300     Wolverine World Wide, Inc.                           4,560
                                                                   ----------
                                                                      10,925
                                                                   ----------

EDUCATION--4.5%
       57,600     Apollo Group Inc. Cl A(1)                            1,552
       90,000     Computer Learning Centers, Inc.(1)                   2,385
       86,900     Learning Tree International, Inc.(1)                 2,770
                                                                   ----------
                                                                       6,707
                                                                   ----------

ELECTRICAL & ELECTRONIC
COMPONENTS--9.1%
       10,000     Burr-Brown Corp.(1)                                    297
       19,000     Cymer, Inc.(1)                                         780
       96,000     II-VI, Inc.(1)                                       1,788
       35,400     Jabil Circuit, Inc.(1)                               1,710
       50,000     NeoMagic Corporation(1)                                584
       59,300     Sanmina Corp.(1)                                     2,969
      100,000     Sipex Corp.(1)                                       2,437
       94,000     Vitesse Semiconductor Corp.(1)                       2,979
                                                                   ----------
                                                                      13,544
                                                                   ----------

ENERGY (SERVICES)--6.9%
       33,200     Atwood Oceanics, Inc.(1)                             2,046
      125,600     Hvide Marine, Inc.(1)                                2,135
      100,000     Marine Drilling Companies, Inc.(1)                   1,587
       46,700     Smith International, Inc.(1)                         2,212
       65,000     Trico Marine Services, Inc.(1)                       2,299
                                                                   ----------
                                                                      10,279
                                                                   ----------

ENTERTAINMENT--1.0%
       50,000     Carmike Cinemas, Inc.(1)                              1,550
                                                                   ----------

See Notes to Financial Statements


8        Schedule of Investments                 American Century Investments


                           SCHEDULE OF INVESTMENTS

APRIL 30, 1997 (UNAUDITED)

Shares                         ($ in Thousands)                         Value
- -----------------------------------------------------------------------------

ENVIRONMENTAL SERVICES--2.8%
      126,400     Superior Services Inc.(1)                       $    2,844
       40,000     United Waste Systems, Inc.(1)                        1,348
                                                                   ----------
                                                                       4,192
                                                                   ----------

HEALTHCARE--2.4%
      112,000     Advanced Health Corp.(1)                             1,904
       49,200     CRA Managed Care, Inc.(1)                            1,747
                                                                   ----------
                                                                       3,651
                                                                   ----------

LEISURE--1.2%
      180,000     Vistana, Inc.(1)                                     1,721
                                                                   ----------

MACHINERY & EQUIPMENT--7.1%
       45,000     CFM Technologies, Inc.(1)                            1,482
       49,350     Diebold, Inc.                                        1,653
      151,500     Intevac, Inc.(1)                                     1,979
      180,000     OmniQuip International, Inc.(1)                      2,385
       99,300     Veeco Instruments Inc.(1)                            3,116
                                                                   ----------
                                                                      10,615
                                                                   ----------

MEDICAL EQUIPMENT & SUPPLIES--1.9%
       74,600     Sabratek Corp.(1)                                    1,627
       68,900     SeaMED Corp.(1)                                      1,163
                                                                   ----------
                                                                       2,790
                                                                   ----------

METALS & MINING--0.9%
       50,000     Titanium Metals Corporation(1)                       1,297
                                                                   ----------

PHARMACEUTICALS--5.3%
       86,000     Dura Pharmaceuticals, Inc.(1)                        2,499
      130,000     Kos Pharmaceuticals, Inc.(1)                         2,941
      103,200     Medicis Pharmaceutical Corp.(1)                      2,535
                                                                   ----------
                                                                       7,975
                                                                   ----------

RESTAURANTS--1.8%
      110,200     Rainforest Cafe, Inc.(1)                             2,610
                                                                   ----------

RETAIL (SPECIALTY)--5.0%
      154,000     Action Performance Cos. Inc.(1)                      4,052
      129,100     Finish Line, Inc.(1)                                 1,331
       67,000     Pacific Sunwear of California(1)                     2,111
                                                                   ----------
                                                                       7,494
                                                                   ----------


Shares/Principal Amount          ($ in Thousands)                       Value
- -----------------------------------------------------------------------------

TOBACCO--2.0%
       60,000     Consolidated Cigar Holdings, Inc.(1)            $    1,380
       65,000     General Cigar Holdings, Inc.(1)                      1,536
                                                                   ----------
                                                                       2,916
                                                                   ----------

TRANSPORTATION--0.4%
       33,000     Eagle USA Airfreight, Inc.(1)                          664
                                                                   ----------

TOTAL COMMON STOCKS--95.5%                                           142,615
                                                                   ----------
   (Cost $157,383)

TEMPORARY CASH INVESTMENTS--4.5%(2)

    $6,800 par value FFCB Discount
                  Note, 5.30%, 5/5/97                                  6,796
                                                                   ----------
   (Cost $6,796)

TOTAL INVESTMENT SECURITIES--100.0%                                 $149,411
                                                                   ==========
   (Cost $164,179)

NOTES TO SCHEDULE OF INVESTMENTS  FFCB = Federal Farm Credit Bank 
(1) Non-income producing.
(2) The rates for U.S. Government Agency discount notes are the yield to
    maturity at purchase.

See Notes to Financial Statements


Semiannual Report                               Schedule of Investments     9


<TABLE>
<CAPTION>
                           STATEMENT OF ASSETS AND LIABILITIES

APRIL 30, 1997 (UNAUDITED)

ASSETS                                        ($ in Thousands Except Per Share Amount)
<S>                                                                              <C>  
Investment securities, at value
(identified cost of $164,179) (Note 3)....................................... $149,411
Cash.........................................................................    1,037
Receivable for investments sold..............................................    1,868
Receivable for capital shares sold...........................................       86
Dividends and interest receivable............................................        3
                                                                              --------
                                                                               152,405
                                                                              --------

LIABILITIES
Payable for investments purchased............................................    4,438
Payable for capital shares redeemed..........................................       15
Accrued management fees (Note 2).............................................      175
                                                                              --------
                                                                                 4,628
                                                                              --------

NET ASSETS APPLICABLE TO OUTSTANDING SHARES.................................. $147,777
                                                                              ========

CAPITAL SHARES, $0.01 PAR VALUE (in Thousands)
Authorized...................................................................  100,000
                                                                              ========

Outstanding..................................................................   36,937
                                                                              ========

Net Asset Value Per Share....................................................    $4.00
                                                                              ========

NET ASSETS CONSIST OF:
Capital (par value and paid in surplus)...................................... $175,465
Undistributed net investment loss............................................    (284)
Accumulated undistributed net realized
loss from investment transactions............................................ (12,636)
Net unrealized depreciation on investments (Note 3).......................... (14,768)
                                                                              --------
                                                                              $147,777
                                                                              ========
</TABLE>

See Notes to Financial Statements


10   Statement of Assets and Liabilities          American Century Investments


<TABLE>
<CAPTION>
                                 STATEMENT OF OPERATIONS

DECEMBER 26, 1996 (INCEPTION) THROUGH APRIL 30, 1997 (UNAUDITED)

INVESTMENT INCOME                                                      ($ in Thousands)

INCOME:
<S>                                                                                <C> 
Interest....................................................................       $234
Dividends...................................................................         13
                                                                              ---------
                                                                                    247
                                                                              ---------
EXPENSES:
Management fees (Note 2)....................................................        530
Directors' fees and expenses................................................          1
                                                                              ---------
                                                                                    531
                                                                              ---------
NET INVESTMENT LOSS.........................................................      (284)
                                                                              ---------

REALIZED AND UNREALIZED LOSS
ON INVESTMENTS (NOTE 3)

Net realized loss...........................................................   (12,636)
Change in net unrealized depreciation.......................................   (14,768)
                                                                              ---------
NET REALIZED AND UNREALIZED LOSS ON INVESTMENTS.............................   (27,404)
                                                                              ---------
NET DECREASE IN NET ASSETS
RESULTING FROM OPERATIONS...................................................  $(27,688)
                                                                              =========
</TABLE>

See Notes to Financial Statements


Semiannual Report                               Statement of Operations    11

<TABLE>
<CAPTION>
                           STATEMENT OF CHANGES IN NET ASSETS

DECEMBER 26, 1996 (INCEPTION) THROUGH
APRIL 30, 1997 (UNAUDITED)

INCREASE IN NET ASSETS

OPERATIONS                                                            ($ in Thousands)
<S>                                                                             <C>   
Net investment loss..........................................................   $(284)
Net realized loss on investments............................................. (12,636)
Change in net unrealized depreciation on investments......................... (14,768)
                                                                              --------
Net decrease in net assets resulting from operations......................... (27,688)
                                                                              --------
CAPITAL SHARE TRANSACTIONS
Proceeds from shares sold....................................................  178,917
Payments for shares redeemed.................................................  (3,452)
                                                                              --------
Net increase in net assets from capital share transactions...................  175,465
                                                                              --------
NET INCREASE IN NET ASSETS...................................................  147,777

NET ASSETS
Beginning of period..........................................................        -
                                                                              --------
End of period................................................................ $147,777
                                                                              ========
Undistributed net investment loss............................................   $(284)
                                                                              ========

TRANSACTIONS IN SHARES OF THE FUND (in Thousands)
Sold.........................................................................   37,693
Redeemed.....................................................................    (756)
                                                                              --------
Net increase.................................................................   36,937
                                                                              ========
</TABLE>

See Notes to Financial Statements


12   Statement of Changes in Net Assets           American Century Investments


                        NOTES TO FINANCIAL STATEMENTS

APRIL 30, 1997 (UNAUDITED)

1. ORGANIZATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

     ORGANIZATION--American  Century  Mutual Funds,  Inc. (the  Corporation)  is
registered under the Investment  Company Act of 1940 as an open-end  diversified
management  investment  company.   American  Century  -  Twentieth  Century  New
Opportunities  Fund (the Fund) is one of the seventeen series of funds issued by
the Corporation.  The Fund's  investment  objective is to seek capital growth by
investing  primarily in common stocks that are  considered by management to have
better-than-average  prospects  for  appreciation.   The  following  significant
accounting  policies  related  to the Fund  are in  accordance  with  accounting
policies generally accepted in the investment company industry.

     SECURITY  VALUATIONS--Portfolio  securities traded primarily on a principal
securities  exchange are valued at the last reported sales price, or the mean of
the  latest  bid and  asked  prices  where no last  sales  price  is  available.
Securities traded  over-the-counter are valued at the mean of the latest bid and
asked prices or, in the case of certain foreign securities, at the last reported
sales price,  depending on local  convention or regulation.  When valuations are
not readily  available,  securities  are valued at fair value as  determined  in
accordance with procedures adopted by the Board of Directors.

     SECURITY TRANSACTIONS--Security  transactions are accounted for on the date
purchased  or  sold.  Net  realized  gains  and  losses  are  determined  on the
identified cost basis, which is also used for federal income tax purposes.

     INVESTMENT  INCOME--Dividend income less foreign taxes withheld (if any) is
recorded as of the ex-dividend date.  Interest income is recorded on the accrual
basis and includes amortization of discounts and premiums.

     FOREIGN  CURRENCY  TRANSACTIONS--The  accounting  records  of the  Fund are
maintained in U.S. dollars.  All assets and liabilities  initially  expressed in
foreign currencies are converted into U.S. dollars at prevailing exchange rates.
Purchases and sales of investment securities,  dividend and interest income, and
certain  expenses  are  translated  at the rates of exchange  prevailing  on the
respective dates of such transactions.

     Net realized foreign currency  exchange gains or losses arise from sales of
foreign  currencies  and the  difference  between  asset and  liability  amounts
initially stated in foreign  currencies and the U.S. dollar value of the amounts
actually  received or paid. Net unrealized  foreign  currency  exchange gains or
losses  arise from  changes in the value of assets and  liabilities,  other than
portfolio securities, resulting from changes in the exchange rates.

     Net realized  and  unrealized  foreign  currency  exchange  gains or losses
occurring  during the holding period of portfolio  securities are a component of
realized gain (loss) on investments and unrealized  appreciation  (depreciation)
on investments, respectively.

     FORWARD  FOREIGN  CURRENCY  EXCHANGE  CONTRACTS--The  Fund may  enter  into
forward foreign currency exchange contracts for the purpose of settling specific
purchases or sales of securities  denominated in a foreign  currency or to hedge
the Fund's  exposure  to  foreign  currency  exchange  rate  fluctuations.  When
required,  the Fund will segregate  assets in an amount  sufficient to cover its
obligations  under the hedge  contracts.  The net U.S.  dollar  value of foreign
currency  underlying  all  contractual  commitments  held  by the  Fund  and the
resulting  unrealized  appreciation or depreciation  are determined  daily using
prevailing exchange rates.  Forward contracts involve elements of risk in excess
of the amount  reflected in the  Statement of Assets and  Liabilities.  The Fund
bears the risk of an unfavorable  change in the foreign  currency  exchange rate
underlying  the  forward  contract.  Additionally,   losses  may  arise  if  the
counterparties do not perform under the contract terms.

     REPURCHASE  AGREEMENTS--The Fund may enter into repurchase  agreements with
institutions  the  Fund's  investment   manager,   American  Century  Investment
Management,  Inc. (ACIM),  has determined are creditworthy  pursuant to criteria
adopted by the Board of  Directors.  Each  repurchase  agree-ment is recorded at
cost.  The  Fund  requires  that  the  securities   purchased  in  a  repurchase
transaction be transferred to the custodian in a manner sufficient to enable the
Fund to obtain those  securities in the event of a default under the  repurchase
agreement.  ACIM  monitors,  on a  daily  basis,  the  value  of the  securities
transferred  to  ensure  that the  value,  including  accrued  interest,  of the
securities  under each repurchase  agreement is equal to or greater than amounts
owed to the Fund under each repurchase agreement.

     JOINT  TRADING  ACCOUNT--Pursuant  to an  Exemptive  Order  issued  by  the
Securities  and  Exchange  Commission,  the Fund,  along with  other  registered
investment   companies  having  management   agreements  with  ACIM  and  Benham
Management  Corporation,  may transfer  uninvested  cash  balances  into a joint
trading  account.  These  balances  are  invested  in  one  or  more  repurchase
agreements that are collateralized by U.S. Treasury or Agency obligations.

     INCOME TAX  STATUS--It is the policy of the Fund to distribute  all taxable
income and capital gains to shareholders and to otherwise qualify as a regulated
investment  company under provisions of the Internal Revenue Code.  Accordingly,
no provision has been made for federal income taxes.


Semiannual Report                         Notes to Financial Statements    13


                        NOTES TO FINANCIAL STATEMENTS

APRIL 30, 1997 (UNAUDITED)

     DISTRIBUTIONS TO  SHAREHOLDERS--Distributions  to shareholders are recorded
on the  ex-dividend  date.  Distributions  from net  investment  income  and net
realized gains are declared and paid annually.

     The  character of  distributions  made during the year from net  investment
income or net realized gains may differ from their ultimate characterization for
federal  income tax purposes.  These  differences  are due to differences in the
recognition  of  income  and  expense  items  for  financial  statement  and tax
purposes.

     SUPPLEMENTARY   INFORMATION--Certain   officers   and   directors   of  the
Corporation are also officers  and/or  directors,  and, as a group,  controlling
stockholders   of  American   Century   Companies,   Inc.,  the  parent  of  the
Corporation's investment manager, ACIM, the Corporation's distributor,  American
Century  Investment  Services,  Inc.,  and  the  Corporation's  transfer  agent,
American Century Services Corporation.

     USE OF  ESTIMATES--The  preparation  of financial  statements in conformity
with  generally  accepted  accounting  principles  requires  management  to make
estimates  and  assumptions  that  affect  the  reported  amounts  of assets and
liabilities  and disclosure of contingent  assets and liabilities at the date of
the financial statements, and the reported amounts of increases and decreases in
net assets from  operations  during the reporting  period.  Actual results could
differ from those estimates.

- --------------------------------------------------------------------------------
2. TRANSACTIONS WITH RELATED PARTIES

     The  Corporation  has entered  into a Management  Agreement  with ACIM that
provides the Fund with investment  advisory and management  services in exchange
for a single,  unified  management fee. The Agreement provides that all expenses
of the Fund, except brokerage commissions,  taxes,  interest,  expenses of those
directors  who  are  not  considered  "interested  persons"  as  defined  in the
Investment  Company  Act of 1940  (including  counsel  fees)  and  extraordinary
expenses, will be paid by ACIM. The fee is computed daily and paid monthly based
on the Fund's  average daily closing net assets during the previous  month.  The
annual management fee is 1.50%.

- --------------------------------------------------------------------------------
3. INVESTMENT TRANSACTIONS

     The aggregate cost of investment securities purchased (excluding short-term
investments) for the six months ended April 30, 1997,  totaled  $207,892,375 for
common stocks.  Proceeds from investment  securities sold (excluding  short-term
investments) totaled $37,873,228 for common stocks.

     As  of  April  30,  1997,  accumulated  net  unrealized   depreciation  was
$14,767,855.  Accumulated  net unrealized  depreciation  consisted of unrealized
appreciation  of $7,768,611  and unrealized  depreciation  of  $22,536,466.  The
aggregate  cost of  investments  for federal income tax purposes was the same as
the cost for financial reporting purposes.

- --------------------------------------------------------------------------------
4. SUBSEQUENT EVENTS
<TABLE>

     The following name changes became effective January 1, 1997:

                       NEW NAMES                                           FORMER NAMES
<S>                   <C>                                                  <C>
Fund's Issuer:        American Century Mutual Funds, Inc.                  Twentieth Century Investors, Inc.
Fund:                 American Century --                                  Twentieth Century New Opportunities Fund
                      Twentieth Century New Opportunities Fund             
Parent Company:       American Century Companies, Inc.                     Twentieth Century Companies, Inc.
Distributor:          American Century Investment Services, Inc.           Twentieth Century Securities, Inc.
Transfer Agent:       American Century Services Corporation                Twentieth Century Services, Inc.
</TABLE>


14   Notes to Financial Statements                  American Century Investments


<TABLE>
<CAPTION>
                                  FINANCIAL HIGHLIGHTS

                               For a Share Outstanding Throughout the Period Indicated

                                                                               1997(1)
PER-SHARE DATA
Net Asset Value,
<S>                                                                             <C>  
Beginning of Period........................................................     $5.00
                                                                             ---------
Income From Investment Operations
     Net Investment Loss...................................................     (0.01)
     Net Realized and Unrealized Loss on Investment Transactions...........     (0.99)
                                                                             ---------
     Total From Investment Operations......................................     (1.00)
                                                                             ---------
Net Asset Value, End of Period.............................................      $4.00
                                                                             =========
     Total Return(2).......................................................   (20.00)%

RATIOS/SUPPLEMENTAL DATA
     Ratio of Operating Expenses to Average Net Assets(3)..................      1.50%
     Ratio of Net Investment Income to Average Net Assets(3)...............    (2.73)%
     Portfolio Turnover Rate...............................................        40%
     Average Commission Paid per Investment Security Traded................    $0.0242
     Net Assets, End of Period (in thousands)..............................   $147,777

(1)  December 26, 1996 (inception) through April 30, 1997 (unaudited).
(2)  Total return assumes reinvestment of dividends and capital gains
     distributions, if any. Total returns for periods less than one year are
     not annualized.
(3)  Annualized.
</TABLE>

See Notes to Financial Statements


Semiannual Report                                  Financial Highlights    15


                       RETIREMENT ACCOUNT INFORMATION

     As required by law, any  distributions  you receive from an IRA and certain
403(b)  distributions [not eligible for rollover to an IRA or to another 403(b)]
are subject to federal  income tax  withholding  at the rate of 10% of the total
amount withdrawn,  unless you elect not to have withholding  apply. If you don't
want us to withhold on this amount, you may send us a written notice not to have
the federal  income tax  withheld.  Your written  notice is valid for six months
from the date of receipt at American Century.  Even if you plan to roll over the
amount you withdraw to another tax-deferred  account, the withholding rate still
applies to the withdrawn  amount unless we have received a written notice not to
withhold federal income tax within six months prior to the withdrawal.

     When you plan to withdraw,  you may make your  election by  completing  our
Exchange/Redemption  form or an IRS Form W-4P. Call American  Century for either
form.  Your  written  election  is valid  for only six  months  from the date of
receipt at American Century. You may revoke your election at any time by sending
a written notice to us.

     Remember, even if you elect not to have income tax withheld, you are liable
for paying income tax on the taxable  portion of your  withdrawal.  If you elect
not to have income tax  withheld or you don't have enough  income tax  withheld,
you may be  responsible  for payment of estimated  tax. You may incur  penalties
under the estimated tax rules if your withholding and estimated tax payments are
not sufficient.


16   Retirement Account Information                 American Century Investments


                                    NOTES


Semiannual Report                                                 Notes    17


                                    NOTES


18   Notes                                       American Century Investments


                                    NOTES


Semiannual Report                                                 Notes    19


                           BACKGROUND INFORMATION

INVESTMENT PHILOSOPHY AND POLICIES

     The  Twentieth  Century  Group  offers nine equity funds that invest in the
stocks  of  growing  companies,  both  domestically  and  internationally.   The
philosophy  behind  these growth funds  focuses on three  important  principles.
First, the funds seek to own successful companies, which we define as those with
growing  earnings  and  revenues.  Second,  we attempt  to keep the funds  fully
invested,  regardless of short-term  market activity.  Experience has shown that
market  gains  can  occur  in  unpredictable   spurts  and  that  missing  those
opportunities can  significantly  limit the potential for gain. Third, the funds
are managed by teams  rather  than by one  "star." We believe  this allows us to
make better, more consistent management decisions.

     In addition to these principles, each fund has its own investment policies.
TWENTIETH CENTURY NEW OPPORTUNITIES generally invests in the securities of small
companies with accelerating  growth. The fund is a volatile investment with high
long-term growth potential.

COMPARATIVE INDICES

     The following  indices are used in the report to serve as fund  performance
comparisons. They are not investment products available for purchase.

     The S&P 500 is a  capitalization-weighted  index of the  stocks  of the 500
largest   publicly  traded  U.S.   companies.   Created  by  Standard  &  Poor's
Corporation,  it is  considered  to be a  broad  measure  of U.S.  stock  market
performance.

     The S&P MIDCAP 400 is a capitalization-weighted  index of the stocks of the
400 largest publicly traded U.S.  companies not included in the S&P 500. Created
by Standard & Poor's Corporation,  it is considered to represent the performance
of mid-cap stocks generally.

     The  RUSSELL  2000  INDEX was  created  by the Frank  Russell  Company.  It
measures  the   performance   of  the  2,000   smallest  of  the  3,000  largest
publicly-traded U.S. companies based on total market capitalization. The Russell
2000 represents  approximately 10% of the total market capitalization of the top
3,000 companies. The average market capitalization of the index is approximately
$420 million.  The Russell 2000 Growth Index  measures the  performance of those
Russell 2000 companies with higher  price-to-book  ratios and higher  forecasted
growth rates.

                      FUND MANAGEMENT TEAM LEADERS
                      Portfolio Manager            Glenn Fogle
                      Portfolio Manager            John Seitzer


20   Background Information                       American Century Investments


                                  GLOSSARY

RETURNS

o    TOTAL RETURN figures show the overall  percentage  change in the value of a
     hypothetical  investment  in the fund  and  assume  that all of the  fund's
     distributions are reinvested.

o    AVERAGE ANNUAL  RETURNS  illustrate  the annually  compounded  returns that
     would have  produced  the  fund's  cumulative  total  returns if the fund's
     performance  had been  constant  over the  entire  period.  Average  annual
     returns smooth out variations in a fund's return;  they are not the same as
     fiscal year-by-year results. For fiscal year-by-year total returns,  please
     refer to the "Financial Highlights" on page 15.

PORTFOLIO STATISTICS

o    NUMBER OF COMPANIES-- the number of different companies held by a fund on a
     given date.

o    AVERAGE  DIVIDEND  YIELD OF  HOLDINGS-- a percentage  return  calculated by
     dividing a company's  annual cash  dividend by the current  market value of
     the company's stock.

o    PRICE/EARNINGS  (P/E)  RATIO--  a stock  value  measurement  calculated  by
     dividing a company's stock price by its earnings per share, with the result
     expressed as a multiple instead of as a percentage.  (Earnings per share is
     calculated  by dividing  the  after-tax  earnings of a  corporation  by its
     outstanding shares.)

o    PORTFOLIO  TURNOVER-- the percentage of a fund's investment  portfolio that
     is replaced during a given time period,  usually a year.  Actively  managed
     portfolios tend to have higher turnover than passively  managed  portfolios
     such as index funds.

o    EXPENSE  RATIO--  the  operating  expenses  of  the  fund  expressed  as  a
     percentage  of average  net assets.  Shareholders  pay an annual fee to the
     investment  manager for investment  advisory and management  services.  The
     expenses and fees are deducted from fund income,  not from each shareholder
     account. (See Note 2 in the Notes to Financial Statements.)


TYPES OF STOCKS

o    BLUE-CHIP  STOCKS--  stocks of the most  established  companies in American
     industry.  They are  generally  large,  fairly stable  companies  that have
     demonstrated   consistent   earnings  and  usually  have  long-term  growth
     potential. Examples include General Electric and Coca-Cola.

o    CYCLICAL  STOCKS--  generally  considered  to be  stocks  whose  price  and
     earnings  fluctuations  tend to follow  the ups and  downs of the  business
     cycle.  Examples  include  the stocks of  automobile  manufacturers,  steel
     producers and textile operators.

o    GROWTH  STOCKS--  stocks of companies that have  experienced  above-average
     earnings  growth and appear  likely to continue  such growth.  These stocks
     often  sell  at high  P/E  ratios.  Examples  can  include  the  stocks  of
     high-tech, healthcare and consumer staple companies.

o    LARGE-CAPITALIZATION  ("LARGE-CAP")  STOCKS--  generally  considered  to be
     stocks of  companies  with a market  capitalization  (the total  value of a
     company's outstanding stock) of more than $5 billion.  These tend to be the
     stocks that make up the Dow Jones Industrial Average and the S&P 500.

o    MEDIUM-CAPITALIZATION ("MID-CAP") STOCKS--generally considered to be
     stocks of companies with a market capitalization (the total value of a
     company's outstanding stock) of between $1 billion and $5 billion. These
     tend to be the stocks that make up the S&P 400.

o    SMALL-CAPITALIZATION  ("SMALL-CAP")  STOCKS--  generally  considered  to be
     stocks of  companies  with a market  capitalization  (the total  value of a
     company's outstanding stock) of less than $1 billion.  These tend to be the
     stocks that make up the Russell 2000 Index.

o    VALUE STOCKS-- generally considered to be stocks that are purchased because
     they are relatively  inexpensive.  These stocks are typically characterized
     by low P/E ratios.

STATISTICAL TERMINOLOGY


o    PRICE/BOOK  RATIO-- a stock  value  measurement  calculated  by  dividing a
     company's  stock  price by its  book  value  per  share,  with  the  result
     expressed as a multiple  instead of as a percentage.  (Book value per share
     is calculated by subtracting a company's  liabilities from its assets, then
     dividing that value by the number of outstanding shares.)


Semiannual Report                                              Glossary    21


[american century logo]
American
Century(sm)

P.O. Box 419200
Kansas City, Missouri
64141-6200

Investor Services:
1-800-345-2021 or 816-531-5575

Automated Information Line:
1-800-345-8765

Telecommunications Device for the Deaf:
1-800-634-4113 or 816-753-1865

Fax: 816-340-7962

Internet: www.americancentury.com


AMERICAN CENTURY MUTUAL FUNDS, INC.

Investment Manager
AMERICAN CENTURY INVESTMENT MANAGEMENT, INC.
Kansas City, Missouri

This report and the financial  statements contained herein are submitted for the
general  information  of our  shareholders.  The  report is not  authorized  for
distribution  to  prospective  investors  unless  preceded or  accompanied by an
effective prospectus.

American Century Investment Services, Inc.

9706           [recycled logo]
SH-BKT-8635       Recycled
<PAGE>
                                SEMIANNUAL REPORT

                            [american century logo]
                                    American
                                  Century(sm)

                                 April 30, 1997

                                     BENHAM
                                      GROUP

                                  Cash Reserve

[front cover]


                               TABLE OF CONTENTS

Report Highlights........................................... 1
Our Message to You.......................................... 2
Period Overview............................................. 3
Corporate Credit Review..................................... 4
Performance & Portfolio Information......................... 5
Management Q & A............................................ 6
Schedule of Investments..................................... 8
Statement of Assets and Liabilities.........................11
Statement of Operations.....................................12
Statements of Changes in Net Assets.........................13
Notes to Financial Statements...............................14
Financial Highlights........................................17
Share Class and Retirement
Account Information.........................................18
Background Information
     Investment Philosophy & Policies.......................20
     Comparative Indices....................................20
     Lipper Rankings........................................20
     Portfolio Management Team..............................20
     Credit Research Team...................................20
Glossary....................................................21

American Century  Investments offers you nearly 70 fund choices covering stocks,
bonds, money markets,  specialty investments and blended portfolios. To help you
find the funds that may meet your needs, we have divided  American Century funds
into three groups based on investment style and objectives.  These groups, which
appear below, are designed to help simplify your fund decisions.

                  American Century Investments--Family of Funds

     BENHAM GROUP           AMERICAN CENTURY GROUP       TWENTIETH CENTURY GROUP

  MONEY MARKET FUNDS          ASSET ALLOCATION &
 GOVERNMENT BOND FUNDS        BALANCED FUNDS                U.S. GROWTH FUNDS
DIVERSIFIED BOND FUNDS   CONSERVATIVE EQUITY FUNDS         INTERNATIONAL FUNDS
 MUNICIPAL BOND FUNDS         SPECIALTY FUNDS

     Cash Reserve

We welcome your comments or questions about this report.  
See the back cover for ways to contact us by mail, phone or e-mail.

Twentieth  Century and the Benham Group are registered marks of American Century
Services Corporation and Benham Management Corporation,  respectively.  American
Century is a service mark of American Century Services Corporation.


                                                    American Century Investments


                               REPORT HIGHLIGHTS

PERIOD OVERVIEW

o    U.S.  economic  growth  accelerated  during the six months  ended April 30,
     1997, while inflation remained relatively subdued.

o    The Federal Reserve raised  short-term  interest rates in March to head off
     potential inflation and slow the rapid pace of economic growth.

o    As a direct result of the Fed's  increase in short-term  rates,  U.S. money
     market yields rose during the six-month period.

o    The market anticipated the Fed rate hike--money market yields rose steadily
     in the weeks prior to the Fed's action.

o    Money market  yields  leveled off in April as mixed  economic  signals cast
     doubts about future Fed interest rate policy. 

CORPORATE CREDIT REVIEW

o    A strong U.S. economy led to improved  corporate credit  conditions  during
     the six-month period.

o    Despite the generally  positive credit  conditions,  many  "sub-prime" auto
     lenders--so  called  because they make loans to borrowers  with poor credit
     histories--defaulted on debt payments or suffered credit rating downgrades.

o    The Japanese  banking system  continued to struggle under the weight of bad
     real estate loans and sluggish loan activity.

CASH RESERVE

o    According to Lipper Analytical Services,  the fund outperformed the average
     money market fund during the six months ended April 30, 1997.

o    The fund was positioned  defensively throughout the period, with an average
     maturity of 40-45 days.

o    The fund's short  maturity  enabled it to quickly  reflect the Fed interest
     rate increase in March.

o    Some money market funds were hit by defaults and rating  downgrades on debt
     issued by sub-prime auto lenders, but the fund was unaffected because these
     issuers failed to meet our strict credit criteria.

o    Going  forward,  we expect  short-term  interest  rates to trend  higher as
     economic growth remains healthy.

                                  Cash Reserve
                               INVESTOR CLASS(1)
                      Total Returns:           AS OF 4/30/97
                         6 Months                   2.40%(2)
                         1 Year                        4.89%

                      7-Day Current Yield:             4.94%
                         (AS OF 4/30/97)

                      Net Assets:               $1.2 billion
                         (AS OF 4/30/97)

                      Inception Date:                 3/1/85

                      Ticker Symbol:                   TWCXX

                      (1) See Share Classes, page 18.
                      (2) Not annualized.

                 Many of the investment terms in this report are
                       defined in the Glossary on page 21.


Semiannual Report                                         Report Highlights    1


                               OUR MESSAGE TO YOU

[photo of James E. Stowers III and James M. Benham]

April 30,  1997,  marked the end of an eventful  period for our company and U.S.
money  market  rates.  Over the past six months,  money market rates rose as the
Federal  Reserve  raised  short-term   interest  rates  to  head  off  potential
inflation.  In the following  pages,  our  investment  management  team provides
further  details  about the  market  and how your fund was  managed  during  the
period.

In January,  nearly two years of integration  between  Twentieth Century and The
Benham  Group   culminated  when  we  began  serving  you  as  American  Century
Investments.  Under this new name we have  combined  our  offerings of nearly 70
funds.

The new name also introduces three new groupings for the funds--the Benham Group
(money market and bond funds),  the American  Century  Group (asset  allocation,
balanced,  conservative  equity and specialty  funds) and the Twentieth  Century
Group  (aggressive  growth and  international  equity  funds).  Cash Reserve has
joined the Benham Group  because its  investment  goals--current  income and the
preservation of principal--match key attributes of that group.

By now,  you should have  received a proxy  statement  and  ballot;  we strongly
encourage  you to read it carefully  and take part in the proxy vote if you have
not already done so.

In  reviewing  this report,  you may notice some  changes.  Based on  investors'
feedback,  our  shareholder  reports have been  redesigned  with added features,
including a report  summary,  a glossary,  more charts and graphs,  and expanded
management  Q&A  and  background  information  sections.  All  American  Century
shareholder reports have been converted to this format.

During  the past  year,  we also  began to offer two  classes of shares for many
funds,  including Cash Reserve.  One class (the Investor  Class) is designed for
investors  who buy  directly  from us,  and the  other  (the  Advisor  Class) is
designed for investors who buy through certain financial  intermediaries.  We've
introduced the Advisor Class so financial  intermediaries can be compensated for
the additional  services they provide.  (See page 18 for more information  about
share classes.)

These are  examples  of how we  continue  working  to  provide  information  and
services  that are useful and  convenient  to  investors  in our funds.  We look
forward to sharing other helpful changes with you.

Sincerely,

/s/James E. Stowers III                     /s/James M. Benham
James E. Stowers III                        James M. Benham
President and Chief Executive Officer       Vice Chairman
American Century Companies                  American Century Companies


2    Our Message to You                             American Century Investments


                                PERIOD OVERVIEW

U.S. Economy

U.S.  economic  growth  accelerated  during the six months ended April 30, 1997.
After moderating throughout the summer of 1996, economic growth rebounded in the
fourth quarter as strong employment  growth,  increased  consumer spending and a
robust housing market fueled an annualized growth rate of 3.8%. The U.S. economy
continued to pick up speed in the first quarter of 1997, surging ahead at a 5.8%
annual rate.

Although  such  a  strong  level  of  economic  growth  has  historically   been
accompanied by rising prices,  inflation  remained under  control--the  consumer
price  index rose at an annual  rate of 3.2% during the  six-month  period.  But
recent  evidence of  increasing  wage  pressures--which  are often  passed on to
consumers  in the form of  higher  prices--led  the  Federal  Reserve  to make a
pre-emptive  strike against  inflation by raising  short-term  interest rates in
March. The Fed raised its federal funds rate target (the overnight  lending rate
targeted  by the Fed for large  loans  between  commercial  banks) from 5.25% to
5.50%.

Money Market Securities

Money market  yields  pushed  higher during the six months ended April 30, 1997.
The  three-month  Treasury  bill yield rose from 5.15% at the  beginning  of the
period to 5.25% on April 30, but it  fluctuated  between  4.92% and 5.40% during
the period.  The overall  increase in money market rates was a direct  result of
the Fed's short-term interest rate increase in March.

The accompanying  graph  illustrates the change in money market rates during the
period.  The graph  features  the  three-month  London  Interbank  Offered  Rate
(LIBOR),  a money  market  rate that  most  banks and  corporations  track  when
determining  the rate they'll pay to investors on short-term  debt.  Three-month
LIBOR  has  typically  reflected  the money  market's  future  expectations  for
short-term interest rates. As the graph illustrates,  the market anticipated the
Fed's action in  March--three-month  LIBOR rose steadily in the weeks leading up
to the Fed interest rate increase.

Money  market  yields  continued  to rise  after the Fed rate  hike,  reflecting
expectations  of further Fed interest  rate  increases in 1997.  However,  mixed
economic  signals in April cast doubt on this  outlook and helped  money  market
yields stabilize by the end of the period.

[line graph - data below]

                FEDERAL FUNDS RATE TARGET VS. THREE-MONTH LIBOR
                         October '96 through April '97

                   Three-Month LIBOR       Fed Funds Rate Target

10/31/96                  5.5%                      5.25%
11/8/96                   5.5                       5.25
11/15/96                  5.5                       5.25
11/22/96                  5.5                       5.25
11/29/96                  5.5                       5.25
12/6/96                   5.54688                   5.25
12/13/96                  5.55078                   5.25
12/20/96                  5.59375                   5.25
12/27/96                  5.61719                   5.25
1/3/97                    5.5625                    5.25
1/10/97                   5.5625                    5.25
1/17/97                   5.5625                    5.25
1/24/97                   5.5625                    5.25
1/31/97                   5.5625                    5.25
2/7/97                    5.54297                   5.25
2/14/97                   5.49609                   5.25
2/21/97                   5.47266                   5.25
2/28/97                   5.53906                   5.25
3/7/97                    5.5625                    5.25
3/14/97                   5.59766                   5.25
3/21/97                   5.71875                   5.25
3/28/97                   5.77344                   5.5
4/4/97                    5.8125                    5.5
4/11/97                   5.81641                   5.5
4/18/97                   5.83594                   5.5
4/25/97                   5.85156                   5.5
4/30/97                   5.81641                   5.5
Source: DRI/McGraw Hill


Semiannual Report                                           Period Overview    3


                            CORPORATE CREDIT REVIEW

A strong U.S. economy led to improved corporate credit conditions during the six
months ended April 30, 1997. Steady corporate  earnings growth  contributed to a
record number of corporate  credit  rating  upgrades.  According to  bond-rating
agency Moody's Investors Service, upgrades outpaced downgrades in 1996 by 283 to
184, a ratio of 3 to 2.

Specific  industries  benefiting  from the  upgrade  trend  included  industrial
companies,  most recently in the airline sector. In the financial sector,  banks
remained  stable and strong  after  several  years of credit  upgrades,  while a
rising stock market and heavy initial public offering  activity  translated into
upgrades for brokerage firms.

Despite the favorable credit environment,  we continue to monitor a few negative
credit trends  evident  during the period.  Two problem areas  highlight how our
proactive and  conservative  approach to credit  analysis helps limit the fund's
credit risk.

So far in 1997,  several  "sub-prime" auto lenders-- so called because they make
loans to borrowers with poor credit  histories--have  defaulted on debt payments
or experienced credit rating downgrades.  For example,  sub-prime lender Mercury
Finance defaulted on its debt payments, even though Mercury's direct debt issues
were considered "tier 1" according to SEC standards.

The SEC defines a "tier 1" security  as an issue that has  received  the highest
possible  short-term rating from two independent rating agencies.  Our standards
for  considering  a security  for purchase are more  stringent;  Mercury's  debt
failed to clear even the first hurdle in our internal rating process.

Another  development  we're  watching  closely is the ongoing  Japanese  banking
crisis.  Japanese banks have suffered since 1990,  when  speculative  bubbles in
both the  Japanese  real  estate and stock  markets  burst.  Japan's  economy is
recovering  slowly,  while  its  real  estate  and  stock  markets  continue  to
deteriorate.  Surprisingly,  many Japanese banks reported  positive earnings for
the fiscal year ended March 31,  largely  because  they wrote off fewer bad real
estate loans than in previous years.

But Japanese  banks are not out of the woods yet. They still face some lingering
bad real estate debt,  as well as falling  equity  positions  and sluggish  loan
activity.  In addition,  Japanese interest rates are expected to rise later this
year,  which would raise the funding costs of Japanese  banks and cut into their
interest income.

When the banking  crisis was at its peak, the Japanese  government  announced it
would back the 20 largest  Japanese  banks.  We've pared down that list of 20 to
only those banks that can function  independently.  In practice,  that means the
list of Japanese  banks with which we'll do  business is much  shorter  than the
list of 20 that others find acceptable.  Cash Reserve  currently has no Japanese
bank exposure.

[line graph - data below]

IMPROVING CORPORATE CREDIT QUALITY

              Downgrades             Upgrades
'87               189                   102
'88               237                   138
'89               339                   138
'90               433                   98
'91               350                   119
'92               227                   136
'93               154                   163
'94               160                   183
'95               221                   205
'96               184                   283

Source: Moody's Investors Service


4    Corporate Credit Review                        American Century Investments

<TABLE>
<CAPTION>
                      PERFORMANCE & PORTFOLIO INFORMATION

TOTAL RETURNS AS OF APRIL 30, 1997

                                                                   AVERAGE ANNUAL RETURNS
                                        6 MONTHS         1 YEAR           3 YEARS           5 YEARS       10 YEARS   LIFE OF FUND
INVESTOR CLASS (inception 3/1/85)
<S>                                       <C>             <C>              <C>               <C>            <C>        <C>  
Cash Reserve                              2.40%           4.89%            4.92%             3.94%          5.40%      5.61%
90-Day Treasury Bill Index                2.56%           5.17%            5.22%             4.40%          5.57%      5.76%
Average Money Market
Instrument Fund(1)                        2.35%           4.77%            4.86%             4.03%          5.50%    5.69%(2)
Fund's Ranking Among
Money Market
Instrument Funds(1)                        --      128 out of 293   106 out of 228   115 out of 177  73 out of 106  59 out of 88(2)

ADVISOR CLASS (inception 4/1/97)
Cash Reserve                              0.37%
90-Day Treasury Bill Index                0.43%

(1)  According to Lipper Analytical Services.
(2)  Since 3/31/85,  the date  nearest the fund's  inception  for which data are
     available.
</TABLE>

See pages 20-21 for more information  about returns,  the comparative  index and
Lipper fund rankings.

YIELDS AS OF APRIL 30, 1997

                                          7-DAY             7-DAY
                                         CURRENT          EFFECTIVE
                                          YIELD             YIELD

Cash Reserve                              4.94%             5.06%


Yields are defined in the Glossary on page 21.

PORTFOLIO AT A GLANCE
                                         4/30/97          10/31/96
Number of Securities                       69                84
Weighted Average Maturity                44 days           46 days
Expense Ratio (for Investor Class)       0.70%*             0.70%

* Annualized.

Money market funds are neither insured nor guaranteed by the U.S. government.

Yields will fluctuate,  and there can be no assurance that the fund will be able
to maintain a stable $1.00 share price.


Semiannual Report                       Performance & Portfolio Information    5


                                 MANAGEMENT Q&A

An  interview  with Bob Gahagan and Denise  Tabacco,  portfolio  managers on the
Benham Cash Reserve management team.

How did the fund perform?

The fund outperformed its peer group average. For the six months ended April 30,
1997, the fund's Investor Class shares posted a total return of 2.40%,  compared
with the 2.35% average return of the 304 "Money Market Instrument Funds" tracked
by Lipper Analytical Services. (See the Total Returns table on the previous page
for other fund performance comparisons.)

How was the fund positioned during the period?

We positioned the fund defensively  throughout the six-month period, keeping the
fund's average  maturity  around its neutral range of 40-45 days. This defensive
positioning  was based on our  expectation  of an interest  rate increase by the
Federal  Reserve-- a shorter average  maturity  enables the fund to reinvest its
maturing assets more quickly in higher-yielding  securities.  The Fed ultimately
raised rates in late March, and by the end of the period, the fund's yield fully
reflected the rise in rates.

Some money market funds were hit in early 1997 by defaults and rating downgrades
on debt  issued  by some of the more  aggressive  auto  loan  companies,  called
"sub-prime lenders." Did the fund hold any of these securities?

No. The consistent,  disciplined application of our conservative credit criteria
is one reason we weren't  affected  by the  problems  that  plagued  some of our
competitors.  We simply  don't want to  increase  our credit risk for a slightly
higher  yield.  We rely on our high credit  standards to narrow the list of debt
issuers to those we feel are the most creditworthy. From that exclusive list, we
do our homework to uncover the best yield and return stories.

You  increased  the  fund's  holdings  of  asset-backed  securities.  What's the
attraction?

Asset-backed  securities  enable  the  fund to reach  for  higher  yields  while
retaining  a high degree of credit  quality.  Asset-backed  securities  are debt
securities that represent  ownership in a pool of assets,  such as auto loans or
credit cards.  These  securities  typically  have higher yields than  commercial
paper and CDs, and they generally have very high credit quality

[pie charts]

PORTFOLIO COMPOSITION BY SECURITY TYPE (as of 4/30/97)
Commercial Paper 74%
Floating-Rate Notes 13%
Asset-Backed Securities 5%
U.S. Government Agency
Securities 5%
Certificates of Deposit 3%

PORTFOLIO COMPOSITION BY SECURITY TYPE (as of 10/31/96)
Commercial Paper 73%
U.S. Government Agency
Securities 12%
Floating-Rate Notes 12%
Certificates of Deposit 2%
Asset-Backed Securities 1%


6    Management Q & A                               American Century Investments


                                 MANAGEMENT Q&A

because many carry credit  enhancements,  such as bond  insurance.  Asset-backed
securities are also often overcollateralized, which means the securities contain
more  assets  than  are  required  to pay  off the  debt.  Consistent  with  our
conservative  approach to managing  credit  risk,  we've  added  specialists  in
asset-backed securities to our credit research staff.

What's your outlook for money market rates going forward?

The apparent  strength of the economy should  continue to put upward pressure on
short-term  interest  rates.  Although the blistering pace of economic growth in
the first quarter of 1997 is clearly unsustainable,  we feel that the pieces are
in place for healthy economic growth going forward.

A 28-year high in consumer confidence, the lowest unemployment rate in 23 years,
and solid income growth suggest the possibility of increased  consumer  spending
in the months ahead.  Unless we see convincing evidence of an economic slowdown,
we expect the trend toward higher interest rates to continue.

With  that  outlook  in mind,  how will you  manage  the fund  over the next six
months?

We plan to maintain the fund's  defensive  position in the coming months.  We'll
also look to  maintain or even  increase  the fund's  holdings of  floating-rate
notes. This positioning should enable the fund's yield to quickly reflect rising
interest  rates.  We also expect to  continue  working  closely  with our credit
research staff to uncover value among asset-backed securities.

[pie charts]

PORTFOLIO COMPOSITION BY CREDIT RATING (as of 4/30/97) 
A1+ 77% 
A1 20% 
A2 3%

PORTFOLIO COMPOSITION BY CREDIT RATING (as of 10/31/96) 
A1+ 80% 
A1 18% 
A2 2%


Semiannual Report                                          Management Q & A    7


                            SCHEDULE OF INVESTMENTS

APRIL 30, 1997 (UNAUDITED)

Principal Amount                ($ in Thousands)                        Value
- --------------------------------------------------------------------------------

COMMERCIAL PAPER(1)
BANKING--8.1%
$    2,900    Bil North America, Inc., 5.42%,
                5/21/97                                           $  2,891
    15,000    Galicia Funding Corp., 5.39%,
                5/30/97 (Acquired 3/3/97,
                Cost $14,804)(2)                                    14,935
    16,000    Generale Bank S.A., 5.40%,
                6/3/97                                              15,921
     9,000    IMI Funding Co. (USA), 5.40%,
                6/4/97                                               8,954
    19,500    Morgan (J.P.) & Co. Inc., 5.50%,
                7/9/97                                              19,299
    20,000    National Australia, 5.48%, 7/3/97                     19,804
    15,000    Nordbanken N.A., Inc., 5.42%,
                6/9/97                                              14,909
                                                                    ------
                                                                    96,713
                                                                    ------
CONVENIENCE STORES--0.5%
     6,000    Southland Corp., 5.43%, 5/20/97                        5,983
                                                                    ------
DIVERSIFIED COMPANIES--6.2%
    35,000    General Electric Capital Corp.,
                5.39%, 5/29/97 through
                5/30/97                                             34,850
    15,000    Mitsubishi International, 5.44%,
                6/18/97                                             14,889
    25,000    Mitsubishi International, 5.52%,
                7/17/97                                             24,701
                                                                    ------
                                                                    74,440
                                                                    ------
EDUCATION--0.4%
     5,000    Leland Stanford University, 5.42%,
                6/10/97                                              4,971
                                                                    ------
FINANCIAL SERVICES--20.6%
    25,000    American Express Co., 5.42%,
                5/21/97                                             24,927
    15,000    Ameritech Capital Funding Corp.,
                5.47%, 5/5/97 (Acquired
                11/4/96, Cost $14,600)(2)                           14,991
    27,244    Bass Finance (C.I.) Ltd., 5.46%,
                5/9/97                                              27,212
    10,000    Demir Funding, 5.57%, 7/16/97                          9,881


Principal Amount                ($ in Thousands)                        Value
- --------------------------------------------------------------------------------

$   10,500    Ford Motor Credit, 5.42%,
                6/11/97                                          $  10,434
    12,400    Ford Motor Credit, 5.50%, 7/9/97                      12,267
    20,000    Ford Motor Credit, 5.53%, 7/21/97                     19,747
     8,300    General Motors Acceptance Co.,
                5.45%, 5/15/97                                       8,283
    12,500    General Motors Acceptance Co.,
                5.56%, 8/4/97                                       12,322
    15,000    General Motors Acceptance Co.,
                5.59%, 8/25/97                                      14,743
    11,400    Hitachi Credit America Corp.,
                5.42%, 5/23/97                                      11,363
    20,500    Hitachi Credit America Corp.,
                5.48%, 6/30/97                                      20,307
    24,200    Metlife Funding, Inc., 5.46%,
                5/7/97                                              24,179
    17,251    Metlife Funding, Inc., 5.40%,
                6/3/97                                              17,164
    20,000    Prudential Funding, 5.47%,
                5/5/97                                              19,988
                                                                    ------
                                                                   247,808
                                                                   -------
HOUSEHOLD AUDIO & VIDEO--1.5%
    17,700    Panasonic Finance, 5.40%, 6/3/97
                (Acquired 4/7/97,
                Cost $17,544)(2)                                    17,610
                                                                    ------
INSURANCE--0.4%
     5,300    American Family Mutual Insurance
                Co., 5.45%, 5/15/97                                  5,289
                                                                    ------
MACHINERY--1.1%
    13,750    Dover Corp., 5.43%, 5/20/97                           13,710
                                                                    ------
METALS & MINING--2.6%
    15,000    RTZ America Inc., 5.42%, 6/9/97                       14,912
    14,700    U.S. Borax, Inc., 5.40%, 5/28/97                      14,642
     1,400    U.S. Borax, Inc., 5.46%, 6/23/97                       1,388
                                                                    ------
                                                                    30,942
                                                                    ------
OFFICE EQUIPMENT & SUPPLIES--1.2%
    15,000    Hitachi America, Ltd., 5.47%,
                5/6/97                                              14,989
                                                                    ------
PETROLEUM REFINING--8.5%
    13,000    Chevron Transport, 5.39%,
                5/30/97 (Acquired 3/10/97,
                Cost $12,844)(2)                                    12,944

See Notes to Financial Statements


8    Schedule of Investments                        American Century Investments


                            SCHEDULE OF INVESTMENTS

APRIL 30, 1997 (UNAUDITED)

Principal Amount                ($ in Thousands)                        Value
- --------------------------------------------------------------------------------

$   10,000    Chevron Transport, 5.42%,
                6/10/97 (Acquired 11/13/96,
                Cost $9,693)(2)                                 $    9,941
    15,000    Chevron Transport, 5.43%,
                5/19/97 (Acquired 4/1/97,
                Cost $14,888)(2)                                    14,958
    10,000    Chevron U.K. Investment PLC,
                5.45%, 5/14/97                                       9,980
    14,379    Petroleo Brasileiro S.A., 5.42%,
                5/22/97                                             14,332
    40,000    Statoil-Den Norske Stats, 5.46%,
                5/8/97                                              39,957
                                                                    ------
                                                                   102,112
                                                                   -------
PHARMACEUTICALS--4.1%
    23,000    Bayer Corp., 5.47%, 5/6/97
                (Acquired 2/21/97,
                Cost $22,752)(2)                                    22,983
    26,700    Glaxo Wellcome PLC, 5.46%,
                6/23/97 (Acquired 4/21/97,
                Cost $26,441)(2)                                    26,482
                                                                    ------
                                                                    49,465
                                                                    ------
PUBLISHING--2.1%
    25,000    Reed Elsevier Inc., 5.41%, 6/6/97                     24,866
                                                                    ------
SECURITY BROKERS & DEALERS--9.7%
    25,000    BT Securities Corp., 5.59%,
                8/26/97                                             24,564
    27,000    Goldman Sachs Group L.P., 5.40%,
                5/28/97                                             26,888
    25,000    Merrill Lynch & Co., 5.39%,
                5/30/97                                             24,888
     9,500    Merrill Lynch & Co., 5.42%,
                5/22/97                                              9,469
    10,000    Morgan Stanley Group, Inc., 5.42%,
                5/23/97                                              9,968
    21,000    Morgan Stanley Group, Inc., 5.44%,
                5/16/97                                             20,953
                                                                    ------
                                                                   116,730
                                                                   -------
SOVEREIGN GOVERNMENTS
& AGENCIES--1.0%
    12,000    Canadian Wheat Board, 5.45%,
                5/15/97                                             11,975
                                                                    ------

Principal Amount                ($ in Thousands)                        Value
- --------------------------------------------------------------------------------

TRANSPORTATION--3.6%
$   18,023    Cosco (Cayman) Company, 5.42%,
                5/21/97                                          $  17,968
    25,000    Cosco (Cayman) Company, 5.45%,
                5/13/97                                             24,955
                                                                    ------
                                                                    42,923
                                                                    ------
UTILITIES (ELECTRIC)--1.8%
    21,200    National Rural Utilities Cooperative
                Finance Corp., 5.43%, 6/13/97                       21,059
                                                                    ------
TOTAL COMMERCIAL PAPER--73.4%                                      881,585
                                                                   -------

CERTIFICATES OF DEPOSIT
    10,000    Bankers Trust New York Corp.,
                5.48%, 6/10/97                                      10,000
    30,000    Westdeutsche Landesbank, 5.62%,
                6/2/97                                              30,000
                                                                    ------
TOTAL CERTIFICATES OF DEPOSIT--3.3%                                 40,000
                                                                    ------

OTHER CORPORATE DEBT
    23,750    American  Express  Centurion Bank, 
                VRN, 5.66%,  5/23/97,  resets
                monthly off the 1-month LIBOR 
                minus 0.03% with no caps, final
                maturity 12/23/97                                   23,750
    14,500    First Bank Minneapolis, VRN,
                5.65%, 5/21/97, resets monthly
                off the 1-month LIBOR minus
                0.04% with no caps, final
                maturity 11/19/97                                   14,500
    40,000    General American Life, VRN,
                5.83%, 5/21/97,  resets monthly 
                off the 1-month LIBOR plus 0.20%
                with no caps, final maturity 1/6/98 (Acquired
                1/3/97, Cost $40,000)(2)                            40,000
    22,000    PNC Bank, N.A., VRN, 5.59%,
                5/1/97, resets monthly off the
                1-month LIBOR minus 0.10%
                with no caps, final maturity
                7/1/97                                              21,998
    17,000    PNC Bank, N.A., VRN, 5.59%,
                5/15/97, resets monthly off the
                1-month LIBOR minus 0.10%
                with no caps, final maturity
                5/15/97                                             16,999

See Notes to Financial Statements


Semiannual Report                                   Schedule of Investments    9


                            SCHEDULE OF INVESTMENTS

APRIL 30, 1997 (UNAUDITED)

Principal Amount                ($ in Thousands)                        Value
- --------------------------------------------------------------------------------

$   17,000    Prudential Funding, VRN, 5.65%,
                5/27/97, resets monthly off the
                1-month LIBOR minus 0.04%
                with no caps, final maturity
                11/26/97 (Acquired 11/25/96,
                Cost $17,000)(2)                              $     17,000
    25,000    Wachovia Bank of NC, VRN,
                5.56%, 5/28/97, resets monthly
                off the 1-month LIBOR minus
                0.125% with no caps, final
                maturity 5/28/97                                    24,998
                                                                    ------
TOTAL OTHER CORPORATE DEBT--13.3%                                  159,245
                                                                   -------

ASSET-BACKED SECURITIES
    17,305    Ford Credit Auto Lease Trust,
                Series 1996-1, Class A1, 5.45%,
                11/15/97                                            17,304
     4,043    Ford Credit Auto Owner Trust,
                Series 1996-B, Class A1, 5.51%,
                10/15/97                                             4,043
    25,715    Money Store Inc. (The) Auto
                Grantor Trust, Series 1996-2,
                Class A1, 5.51%, 1/15/98                            25,715
    18,000    WFS Financial Owner Trust, Series
                1997-A, Class A1, 5.63%,
                3/20/98                                             18,000
                                                                    ------
TOTAL ASSET-BACKED SECURITIES--5.4%                                 65,062
                                                                    ------
U.S. GOVERNMENT AGENCY SECURITIES
    25,000    FHLB, VRN, 5.68%, 5/1/97,
                resets daily off the Fed Funds
                rate plus 0.15% with no caps,
                final maturity 8/1/97                               25,000
    30,000    FNMA, MTN, VRN, 5.63%, 5/1/97,
                resets daily off the Fed Funds rate
                plus 0.01% with no caps, final
                maturity 5/5/97                                     30,000
                                                                    ------
TOTAL U.S. GOVERNMENT
AGENCY SECURITIES--4.6%                                             55,000
                                                                    ------
TOTAL INVESTMENT SECURITIES--100.0%                             $1,200,892
                                                                ==========
See Notes to Financial Statements


Notes to Schedule of Investments

FHLB = Federal Home Loan Bank
FNMA = Federal National Mortgage Association
LIBOR = London Interbank Offered Rate
MTN = Medium Term Note

resets = The frequency  with which a  fixed-income  security's  coupon  changes,
based on current market conditions or an underlying index. The more frequently a
security resets,  the less risk the investor is taking that the coupon will vary
significantly from current market rates.

VRN =  Variable  Rate  Note.  Interest  reset  date  is  indicated  and  used in
calculating the weighted  average  portfolio  maturity.  Rate shown is effective
April 30, 1997.

(1)The rates for commercial paper are the yield to maturity at April 30, 1997.

(2)Security  was purchased under Rule 144A or Section 4(2) of the Securities Act
of 1933 or is otherwise restricted as to resale and, unless registered under the
Act or exempted from registration,  may only be sold to qualified  institutional
investors.  The aggregate value of restricted  securities at April 30, 1997, was
$230,565,000, which represented 19.2% of net assets.


10   Schedule of Investments                        American Century Investments


                       STATEMENT OF ASSETS AND LIABILITIES

APRIL 30, 1997 (UNAUDITED)
                                       ($ in Thousands Except Per-Share Amounts)

ASSETS
Investment securities, at value (amortized cost) (Note 3) .........   $1,200,892
Cash ..............................................................        9,919
Interest receivable ...............................................        3,013
                                                                           -----
                                                                       1,213,824
                                                                       ---------

LIABILITIES
Disbursements in excess of demand deposit cash ....................        5,179
Payable for capital shares redeemed ...............................        3,376
Dividends payable .................................................          813
Accrued management fees (Note 2) ..................................          733
Other liabilities .................................................            3
                                                                          ------
                                                                          10,104
                                                                          ------
Net Assets ........................................................   $1,203,720
                                                                      ==========

NET ASSETS CONSIST OF:
Capital (par value and paid in surplus) ...........................   $1,203,800
Accumulated undistributed net realized loss 
   from investment transactions ...................................         (80)
                                                                            ----
                                                                      $1,203,720
                                                                      ==========
Investor Class
Net assets ........................................................   $1,203,070
Shares outstanding ................................................    1,203,150
Net asset value per share .........................................   $     1.00
Advisor Class
Net assets ........................................................   $      650
Shares outstanding ................................................          650
Net asset value per share .........................................   $     1.00

See Notes to Financial Statements


Semiannual Report                       Statement of Assets and Liabilities   11


                             STATEMENT OF OPERATIONS

FOR THE SIX MONTHS ENDED APRIL 30, 1997 (UNAUDITED)

                                                            ($ in Thousands)
INVESTMENT INCOME
Income:
Interest ....................................................    $36,124
                                                                 -------

Expenses:
Management fees (Note 2) ....................................      4,597
Directors' fees and expenses ................................          8
                                                                 -------
                                                                   4,605
                                                                 -------
Net investment income .......................................     31,519
                                                                 -------
NET REALIZED LOSS ON INVESTMENTS (NOTE 3)
Net realized loss on investments ............................        (2)
                                                                 -------
Net Increase in Net Assets Resulting from Operations ........    $31,517
                                                                 =======

See Notes to Financial Statements


12   Statement of Operations                        American Century Investments

<TABLE>
<CAPTION>
                       STATEMENTS OF CHANGES IN NET ASSETS

SIX MONTHS ENDED APRIL 30, 1997 (UNAUDITED)
AND YEAR ENDED OCTOBER 31, 1996

Decrease in Net Assets                                            1997           1996
                                                                    ($ in Thousands)
OPERATIONS
<S>                                                          <C>            <C>        
Net investment income ....................................   $    31,519    $    67,104
Net realized gain (loss) on investments ..................            (2)             2
                                                                  ------         ------
Net increase in net assets resulting from operations .....        31,517         67,106
                                                                  ------         ------

DISTRIBUTIONS TO SHAREHOLDERS From net investment income:
  Investor Class .........................................       (31,517)       (67,104)
  Advisor Class ..........................................            (2)
                                                                  ------         ------
Decrease in net assets from distributions ................       (31,519)       (67,104)
                                                                 -------        ------- 

CAPITAL SHARE TRANSACTIONS (NOTE 3)
Net decrease in net assets from capital share transactions      (143,378)      (122,448)
                                                                --------       -------- 
Net decrease in net assets ...............................      (143,380)      (122,446)

NET ASSETS
Beginning of period ......................................     1,347,100      1,469,546
                                                               ---------      ---------
End of period ............................................   $ 1,203,720    $ 1,347,100
                                                             ===========    ===========
</TABLE>

See Notes to Financial Statements


Semiannual Report                       Statements of Changes in Net Assets   13


                         NOTES TO FINANCIAL STATEMENTS

APRIL 30, 1997 (UNAUDITED)

1. Organization and Summary of Significant Accounting Policies

Organization--American   Century  Mutual  Funds,   Inc.  (the   Corporation)  is
registered under the Investment  Company Act of 1940 as an open-end  diversified
management investment company.  American Century - Benham Cash Reserve Fund (the
Fund) is one of the  seventeen  series of funds issued by the  Corporation.  The
Fund's investment  objective is to obtain maximum current income consistent with
the preservation of principal and maintenance of liquidity.  The Fund intends to
pursue its investment objective by investing  substantially all of its assets in
a portfolio of money  market  instruments  and  maintaining  a weighted  average
maturity of not more than 90 days. On September 3, 1996, the Fund  implemented a
multiple class structure  whereby the Fund is authorized to issue two classes of
shares:  The Investor Class and the Advisor Class. The shares  outstanding prior
to September 3, 1996, are  designated as Investor Class shares.  The two classes
of shares differ principally in their respective  shareholder servicing fees and
distribution  fees.  All shares of the Fund represent an equal pro rata interest
in the Fund and have identical  voting,  dividend,  liquidation and other rights
and the same  terms and  conditions,  except  for class  specific  expenses  and
exclusive rights to vote on matters affecting only individual  classes.  Sale of
the  Advisor  Class  commenced  on  April 1,  1997.  The  following  significant
accounting  policies,  related to the Fund,  are in accordance  with  accounting
policies generally accepted in the investment company industry.

Security Valuations--Securities are valued at amortized cost, which approximates
current value. When valuations are not readily available,  securities are valued
at fair value as determined in accordance with  procedures  adopted by the Board
of Directors.

Security  Transactions--Security  transactions  are  accounted  for on the  date
purchased  or  sold.  Net  realized  gains  and  losses  are  determined  on the
identified cost basis, which is also used for federal income tax purposes.

Investment Income--Interest income is recorded on the accrual basis and includes
amortization  of discounts  and  premiums.  Discounts and premiums are amortized
daily on a straight-line basis.

Repurchase  Agreements--The  Fund may  enter  into  repurchase  agreements  with
institutions  the  Fund's  investment   manager,   American  Century  Investment
Management,  Inc. (ACIM),  has determined are creditworthy  pursuant to criteria
adopted by the Board of  Directors.  Each  repurchase  agreement  is recorded at
cost.  The  Fund  requires  that  the  securities   purchased  in  a  repurchase
transaction be transferred to the custodian in a manner sufficient to enable the
Fund to obtain those  securities in the event of a default under the  repurchase
agreement.  ACIM  monitors,  on a  daily  basis,  the  value  of the  securities
transferred  to  ensure  that the  value,  including  accrued  interest,  of the
securities  under each repurchase  agreement is equal to or greater than amounts
owed to the Fund under each repurchase agreement.

Joint Trading  Account--Pursuant  to an Exemptive Order issued by the Securities
and  Exchange  Commission,  the Fund,  along  with other  registered  investment
companies  having   management   agreements  with  ACIM  and  Benham  Management
Corporation, may transfer uninvested cash balances into a joint trading account.
These  balances  are  invested  in one or more  repurchase  agreements  that are
collateralized by U.S. Treasury or Agency obligations.

Income Tax Status--It is the policy of the Fund to distribute all taxable income
and net capital gains to  shareholders  and to otherwise  qualify as a regulated
investment  company under provisions of the Internal Revenue Code.  Accordingly,
no provision has been made for federal income taxes.

Distributions--Distributions  from net investment  income are declared daily and
distributed  monthly.  The Fund does not expect to realize any long-term capital
gains, and accordingly, does not expect to pay any capital gains distributions.

Supplementary Information--Certain officers and directors of the Corporation are
also officers and/or  directors,  and, as a group,  controlling  stockholders of
American Century  Companies,  Inc., the parent of the  Corporation's  investment
manager,  ACIM,  the  Corporation's  distributor,  American  Century  Investment
Services,  Inc., ACIS, and the  Corporation's  transfer agent,  American Century
Services Corporation.

Use of  Estimates--The  preparation of financial  statements in conformity  with
generally accepted  accounting  principles requires management to make estimates
and assumptions  that affect the reported  amounts of assets and liabilities and
disclosure of  contingent  assets and  liabilities  at the date of the financial
statements,  and the reported  amounts of increases  and decreases in net assets
from operations  during the reporting  period.  Actual results could differ from
those estimates.


14   Notes to Financial Statements                  American Century Investments


                         NOTES TO FINANCIAL STATEMENTS

APRIL 30, 1997 (UNAUDITED)

- --------------------------------------------------------------------------------
2. Transactions with Related Parties

The Corporation has entered into a Management  Agreement with ACIM that provides
the Fund with  investment  advisory  and  management  services in exchange for a
single,  unified  management  fee per class.  The  Agreement  provides  that all
expenses of the Fund, except brokerage commissions, taxes, interest, expenses of
those  directors who are not considered  "interested  persons" as defined in the
Investment  Company  Act of 1940  (including  counsel  fees)  and  extraordinary
expenses, will be paid by ACIM. The fee is computed daily and paid monthly based
on each Fund's average daily closing net assets during the previous  month.  The
annual  management  fee for each class is 0.70% and 0.45% for the Investor Class
and Advisor Class, respectively.

The Board of Directors has adopted a shareholder  services and distribution plan
for the Advisor Class,  pursuant to Rule 12b-1 of the Investment  Company Act of
1940.  The Advisor  Class Master  Distribution  and  Shareholder  Services  Plan
provides that the Fund will pay ACIM an annual  distribution  fee equal to 0.25%
and service fee equal to 0.25%.  The fees are  computed  daily and paid  monthly
based on the  Advisor  Class's  average  daily  closing  net  assets  during the
previous month.  The  distribution  fee provides  compensation  for distribution
expenses  incurred in connection with  distributing  shares of the Advisor Class
including,  but not limited to,  payments to  brokers,  dealers,  and  financial
institutions  that have entered into sales agreements with ACIS and/or ACIM. The
service fee provides  compensation for shareholder and  administrative  services
rendered by ACIM,  its  affiliates or independent  third party  providers.  Fees
incurred under the Master Distribution and Shareholder  Services Plan during the
period April 1, 1997  (commencement  of sale of Advisor class) through April 30,
1997, were $221.


Semiannual Report                             Notes to Financial Statements   15


                         NOTES TO FINANCIAL STATEMENTS

APRIL 30, 1997 (UNAUDITED)

- --------------------------------------------------------------------------------
3. Capital Share Transactions

There are  2,000,000,000  and  1,000,000,000  shares of the  Investor  Class and
Advisor Class  authorized for issuance,  respectively.  All shares are $0.01 par
value. Transactions in shares of the Fund were as follows:

                                               Shares         Amount
                                                  (In Thousands)
INVESTOR CLASS Six Months Ended April 1, 1997:
Sold ...................................     1,294,912    $ 1,294,912
Issued in reinvestment of distributions         30,592         30,592
Redeemed ...............................    (1,469,532)    (1,469,532)
                                            ----------     ---------- 
Net increase ...........................      (144,028)   $  (144,028)
                                              ========    =========== 

Year Ended October 31, 1996:
Sold ...................................     2,137,139    $ 2,137,139
Issued in reinvestment of distributions         64,608         64,608
Redeemed ...............................    (2,324,195)    (2,324,195)
                                            ----------     ---------- 
Net increase ...........................      (122,448)   $  (122,448)
                                              ========    =========== 

ADVISOR CLASS
April 1, 1997(1) through April 30, 1997:
Sold ...................................           648    $       648
Issued in reinvestment of distributions              2              2
                                            ----------     ---------- 
Net increase ...........................           650    $       650
                                              ========    =========== 
(1) Commencement of sale of the Advisor Class.

- --------------------------------------------------------------------------------
4. Corporate Events

The following name changes became effective January 1, 1997:
<TABLE>

                    NEW NAMES                                     FORMER NAMES
<S>               <C>                                             <C> 
Fund's Issuer:      American Century Mutual Funds, Inc.           Twentieth Century Investors, Inc.
Fund:               American Century - Benham Cash Reserve Fund   Cash Reserve
Parent Company:     American Century Companies, Inc.              Twentieth Century Companies, Inc.
Distributor:        American Century Investment Services, Inc.    Twentieth Century Securities, Inc.
Transfer Agent:     American Century Services Corporation         Twentieth Century Services, Inc.
</TABLE>


16   Notes to Financial Statements                  American Century Investments

<TABLE>
<CAPTION>
                              FINANCIAL HIGHLIGHTS

 For a Share Outstanding Throughout the Years Ended October 31 (except as noted)

                             Investor                                Advisor
                               Class                                  Class

                                       1997(1)     1996       1995       1994      1993(2)    1992(2)    1997(3)

PER-SHARE DATA
Net Asset Value,
<S>                                    <C>         <C>        <C>        <C>          <C>       <C>        <C>  
Beginning of Period .................  $1.00       $1.00      $1.00      $1.00        $1.00     $1.00      $1.00
                                       -----       -----      -----      -----        -----     -----      -----
Income From Investment Operations                                                  
  Net Investment Income .............   0.02        0.05       0.05       0.03         0.02      0.04       --
                                        ----        ----       ----       ----         ----      ----      -----
Distributions                                                                      
  From Net Investment Income ........  (0.02)      (0.05)     (0.05)     (0.03)       (0.02)    (0.04)      --
                                        ----        ----       ----       ----         ----      ----      -----
Net Asset Value, End of Period ......  $1.00       $1.00      $1.00      $1.00        $1.00     $1.00      $1.00
                                       =====       =====      =====      =====        =====     =====      =====
  Total Return(4) ...................   2.40%       4.99%      5.38%      3.21%        2.30%     3.74%      0.37%
                                                                                   
RATIOS/SUPPLEMENTAL RATIOS                                                         
Ratio of Expenses to                                                               
Average Net Assets .................. 0.70%(5)      0.70%      0.70%      0.80%        1.00%   0.98%(6)   0.95%(5)
Ratio of Net Investment Income                                                     
to Average Net Assets ............... 4.77%(5)      4.88%      5.27%      3.18%        2.30%      3.62%   4.70%(5)
Net Assets End                                                                     
of Period (in thousands) ...........$1,203,720  $1,347,106  $1,469,546  $1,298,982 $1,256,012  $1,487,961    $650 
                                                                                
                                                                                
(1)  Six months ended April 30, 1997 (unaudited).

(2)  The data  presented  has been  restated to give effect to a 100 for 1 stock
     split in the form of a stock dividend that occurred on November 13, 1993.

(3)  April 1, 1997  (commencement  of sale of Advisor  Class)  through April 30,
     1997 (unaudited).

(4)  Total  return   assumes   reinvestment   of  dividends  and  capital  gains
     distributions, if any. Total returns for periods less than one year are not
     annualized.

(5)  Annualized.  

(6)  Expenses  are shown  net of  management  fees  waived  by the  manager  for
     low-balance account fees collected during the period.
</TABLE>

See Notes to Financial Statements


Semiannual Report                                      Financial Highlights   17


                       SHARE CLASS AND RETIREMENT ACCOUNT
                                  INFORMATION

Share Classes

Until  September  3,  1996,  Cash  Reserve  issued  one  class  of fund  shares,
reflecting  the fact that most  investors  bought  their  shares  directly  from
American Century.  All investors paid the same annual unified management fee and
did not pay any  commissions  or other fees to  purchase  shares  from  American
Century.

But increasing numbers of investors are purchasing fund shares through financial
intermediaries who are ordinarily  compensated for the additional  services they
provide. In September, American Century began to offer two classes of shares for
Cash  Reserve.  One class is for  investors who still buy directly from American
Century, the other for investors who buy through financial intermediaries.

The original  class of Cash Reserve  shares is called the  Investor  Class.  All
shares issued and outstanding  before September 3, 1996, have been designated as
Investor  Class  shares.  Investor  Class  shares may still be  purchased  after
September 3, 1996.  Investor Class  shareholders  do not pay any  commissions or
other fees for purchase of fund shares directly from American Century. Investors
who buy Investor Class shares through a broker-dealer may be required to pay the
broker-dealer a transaction fee.

In  addition,   there  is  an  Advisor  Class,  which  is  sold  through  banks,
broker-dealers,  insurance  companies  and  financial  advisors.  Advisor  Class
shares,  which  commenced  sales on April 1, 1997,  are  subject to a 0.50% Rule
12b-1  service and  distribution  fee.  Half of that fee is available to pay for
recordkeeping  and  administrative  services,  and half is  available to pay for
distribution  services provided by the financial  intermediary through which the
Advisor Class shares are purchased. The total expense ratio of the Advisor Class
shares  is 0.25%  higher  than the total  expense  ratio of the  Investor  Class
shares.

Both classes of shares  represent a pro rata  interest in the fund and generally
have the same rights and preferences.

Retirement Account Information

As required by law, any distributions you receive from an IRA and certain 403(b)
distributions  [not  eligible for  rollover to an IRA or to another  403(b)] are
subject to federal income tax withholding at the rate of 10% of the total amount
withdrawn,  unless you elect not to have withholding apply. If you don't want us
to withhold  on this  amount,  you may send us a written  notice not to have the
federal  income tax withheld.  Your written  notice is valid for six months from
the date of  receipt  at  American  Century.  Even if you plan to roll  over the
amount you withdraw to another tax-deferred  account, the withholding rate still
applies to the withdrawn  amount unless we have received a written notice not to
withhold federal income tax within six months prior to the withdrawal.

When  you plan to  withdraw,  you may  make  your  election  by  completing  our
Exchange/Redemption  form or an IRS Form W-4P. Call American  Century for either
form.  Your  written  election  is valid  for only six  months  from the date of
receipt at American Century. You may revoke your election at any time by sending
a written notice to us.

Remember,  even if you elect not to have income tax withheld, you are liable for
paying income tax on the taxable portion of your withdrawal. If you elect not to
have income tax withheld or you don't have enough income tax  withheld,  you may
be responsible  for payment of estimated tax. You may incur  penalties under the
estimated  tax rules if your  withholding  and  estimated  tax  payments are not
sufficient.


18 Share Class and Retirement Account Information   American Century Investments


                                     NOTES

Semiannual Report                                                     Notes   19


                             BACKGROUND INFORMATION

Investment Philosophy & Policies

The Benham Group offers 42 fixed-income  funds,  ranging from money market funds
to long-term bond funds and including both taxable and tax-exempt funds.

Cash  Reserve is a money  market fund that seeks to provide  interest  income by
investing in a diversified portfolio of short-term money market securities.  The
fund must maintain a weighted average maturity of 90 days or less.

An  investment  in Cash Reserve is neither  insured nor  guaranteed  by the U.S.
government.  Yields will fluctuate,  and there can be no assurance that the fund
will be able to maintain a stable net asset value of $1 per share.

Comparative Indices

The following index is used in the report as a fund performance  comparison.  It
is not an investment product available for purchase.

The 90-Day  Treasury Bill Index is derived from secondary  market interest rates
as published by the Federal Reserve Bank.

Lipper Rankings

Lipper Analytical  Services,  Inc. is an independent mutual fund ranking service
that groups funds according to their investment  objectives.  Rankings are based
on average  annual  returns  for each fund in a given  category  for the periods
indicated. Rankings are not included for periods less than one year.

The Lipper category for Cash Reserve is:

Money Market Instrument  Funds--funds that intend to maintain a stable net asset
value and that invest in high-quality financial instruments rated in the top two
grades with dollar-weighted average maturities of less than 90 days.


PORTFOLIO MANAGEMENT TEAM
Senior Portfolio Manager            Bob Gahagan
Portfolio Managers                  Amy O'Donnell, Denise Tabacco


CREDIT RESEARCH TEAM
Credit Analysts                     Edward Grant, Tanya Fleischer,
                                    Michael Difley, Tom Vaiana,
                                    John Walsh
Associate Credit
Research Analysts                   Sudha Mani, Richard McClung


20   Background Information                         American Century Investments


                                    GLOSSARY

Returns

o Total  Return  figures  show the overall  percentage  change in the value of a
hypothetical  investment  in  the  fund  and  assume  that  all  of  the  fund's
distributions are reinvested.

o Average Annual Returns  illustrate the annually  compounded returns that would
have produced the fund's cumulative total returns if the fund's  performance had
been  constant  over the  entire  period.  Average  annual  returns  smooth  out
variations  in a fund's  return;  they are not the same as  fiscal  year-by-year
results.  For  fiscal  year-by-year  returns,  please  refer  to the  "Financial
Highlights" on page 17.

Yields

o 7-day  Current  Yield  is  calculated  based  on the  income  generated  by an
investment  in the fund over a seven-day  period and is  expressed  as an annual
percentage rate.

o 7-day  Effective  Yield is  calculated  similarly,  although  this  figure  is
slightly  higher than the fund's 7-Day  Current  Yield because of the effects of
compounding.  The 7-Day  Effective  Yield  assumes  that income  earned from the
fund's investments is reinvested and generating additional income.

Portfolio Statistics

o Number of Securities--the  number of different  securities held by a fund on a
given date.

o  Weighted  Average  Maturity  (WAM)--a  measurement  of the  sensitivity  of a
fixed-income  portfolio to interest rate changes. WAM indicates the average time
until the securities in the portfolio  mature,  weighted by dollar  amount.  The
longer the WAM, the more interest rate  exposure and  sensitivity  the portfolio
has.

o Expense Ratio--the  operating expenses of the fund,  expressed as a percentage
of average net assets.  Shareholders pay an annual fee to the investment manager
for  investment  advisory  and  management  services.  The expenses and fees are
deducted from fund income, not from each shareholder account. (See Note 2 in the
Notes to Financial Statements.)

Types of Money Market Securities

o Asset-Backed Securities--debt securities that represent ownership in a pool of
receivables, such as credit card debt, auto loans or mortgages.

o  Certificates  of Deposit  (CDs)--CDs  represent a bank's  obligation to repay
money deposited with it for a specified  period of time.  Different types of CDs
have different issuers.  For example,  Yankee CDs are issued by U.S. branches of
foreign banks, and Eurodollar CDs are issued in London by Canadian, European and
Japanese banks.

o Commercial Paper  (CP)--short-term  debt issued by large corporations to raise
cash and to cover  current  expenses in  anticipation  of future  revenues.  The
maximum  maturity  for CP is 270 days,  although  most CP is issued in a one- to
50-day  maturity  range.  CP rates  generally track those of other widely traded
money market  instruments,  such as Treasury bills and  certificates of deposit,
but they are also influenced by the maturity date and the size and credit rating
of the issuer.

o Floating-Rate  Notes  (Floaters)--debt  securities whose interest rates change
when a designated  base rate  changes.  The base rate is often the federal funds
rate,  the  90-day  Treasury  bill rate or the  London  Interbank  Offered  Rate
(LIBOR).  Floaters  are  considered  derivatives  because  they  "derive"  their
interest  rates from their  designated  base rates.  However,  floaters  are not
"risky" derivatives--their  behavior is similar to that of their designated base
rates. The SEC has recognized this similarity and does not consider  floaters to
be inappropriate investments for money market funds.

o U.S. Government Agency Notes--intermediate-term debt securities issued by U.S.
government  agencies  (such as the Federal Farm Credit Bank and the Federal Home
Loan  Bank).  Some  agency  notes are backed by the full faith and credit of the
U.S.  government,  while most are guaranteed only by the issuing  agency.  These
notes are issued with  maturities  ranging from three months to 30 years.  Money
market funds invest in these  securities when they have remaining  maturities of
13 months or less.


Semiannual Report                                                  Glossary   21


[american century logo]
American
Century(sm)

P.O. Box 419200
Kansas City, Missouri
64141-6200

Investor Services:
1-800-345-2021 or 816-531-5575

Automated Information Line:
1-800-345-8765

Telecommunications Device for the Deaf:
1-800-634-4113 or 816-444-3485

Fax: 816-340-7962

Internet: www.americancentury.com


AMERICAN CENTURY MUTUAL FUNDS, INC.

Investment Manager
AMERICAN CENTURY INVESTMENT MANAGEMENT


This  report and the  statements  it  contains  are  submitted  for the  general
information of our  shareholders.  The report is not authorized for distribution
to  prospective  investors  unless  preceded  or  accompanied  by  an  effective
prospectus.

American Century Investment Services, Inc.

9706           [recycled logo]
SH-BKT-8695       Recycled
<PAGE>
                                SEMIANNUAL REPORT

                            [american century logo]
                                    American
                                  Century(sm)

                                 APRIL 30, 1997

                                    AMERICAN
                                     CENTURY
                                      GROUP

                                    Balanced


[front cover]


                               TABLE OF CONTENTS

Report Highlights ...................................................... 1
Our Message to You ..................................................... 2
Period Overview ........................................................ 3
Performance & Portfolio Information .................................... 4
Management Q & A ....................................................... 5
Schedule of Investments ................................................ 8
Statement of Assets and Liabilities ....................................12
Statement of Operations ................................................13
Statements of Changes in Net Assets ....................................14
Notes to Financial Statements ..........................................15
Financial Highlights ...................................................19
Share Class and Retirement Account
   Information .........................................................21
Background Information
     Investment Philosophy and Policies ................................24
     Comparative Indices ...............................................24
     Fund Management Team Leaders ......................................24
Glossary ...............................................................25
                                          
American Century  Investments offers you nearly 70 fund choices covering stocks,
bonds, money markets,  specialty investments and blended portfolios. To help you
find the funds that may meet your needs, we have divided  American Century funds
into three groups based on investment style and objectives.  These groups, which
appear below, are designed to help simplify your fund decisions.


                          American Century Investments

      Benham                   American Century        Twentieth Century(R)
     Group(R)                       Group                     Group

  MONEY MARKET FUNDS          ASSET ALLOCATION &           GROWTH FUNDS
 GOVERNMENT BOND FUNDS          BALANCED FUNDS          INTERNATIONAL FUNDS
DIVERSIFIED BOND FUNDS     CONSERVATIVE EQUITY FUNDS
 MUNICIPAL BOND FUNDS           SPECIALTY FUNDS

                                   Balanced


We welcome your comments or questions about this report.  
See the back cover for ways to contact us by mail, phone or e-mail.

Twentieth  Century and the Benham Group are registered marks of American Century
Services Corporation and Benham Management Corporation,  respectively.  American
Century is a service mark of American Century Services Corporation.

                                                    American Century Investments



                               REPORT HIGHLIGHTS

Period Overview

o The U.S. stock market produced widely divergent  returns over the period.  The
S&P  500's  14.74%  six-month  total  return  continued  a  three-year  trend of
unusually strong  performance by large-cap stocks.  By contrast,  the S&P MidCap
400 posted a 6.88% return,  and the small-cap  Russell 2000 returned just 1.61%.
Factors that were in the S&P 500's favor included:  investors  seeking stability
and liquidity; strong economic growth with low inflation; and the success of S&P
500 index funds.

o The shares of fast-growing  mid- and small-cap growth companies didn't benefit
from the  factors  that drove  investors  to the S&P 500.  They  lagged  despite
reporting strong earnings growth in many cases.

o U.S. bonds produced  modest returns during the period.  Rising  interest rates
caused  bond prices to fall,  but the  interest  income paid out to  bondholders
offset  the price  declines  for the most  part.  Short-term  securities,  which
usually suffer less price depreciation than longer term securities when interest
rates are rising, were the best performers during the period. 

Balanced

o Balanced's total return was 1.94%,  reflecting the combined performance of the
fund's stock and bond  components.  The fund's bond portfolio nearly matched the
general  performance of bonds during the period, but the fund's equity portfolio
significantly underperformed the equity returns of its benchmark index.

This   underperformance   resulted   from  the  fund's   weighting  in  smaller,
faster-growing stocks, which declined sharply during the period.

o The fund's holdings in  energy-related  companies proved  disappointing as oil
and gas prices fell. The fund managers continue to like technology stocks due to
their  attractive  earnings and revenue growth;  however,  their valuations were
depressed during the period by skeptical investors and analysts who feared these
companies could not sustain their growth rates.

o Management  increased the equity portfolio's average market  capitalization by
adding more quality mid-cap stocks.  The fund managers  believe these securities
will  provide  a measure  of  growth  and also  lend  greater  stability  to the
portfolio.   In  addition,   management  increased  holdings  in  pharmaceutical
companies to take advantage of a new cycle of product introductions.

o Balanced's  bond portfolio  performed as well as could be expected in a period
that  was not  favorable  for  bonds.  The  portfolio  team  assumed  a  steady,
conservative approach,  keeping the port-folio's duration at or below the fund's
neutral level for much of the period. This short duration proved to be a benefit
in the relatively volatile interest rate environment.

o During the period,  the  difference in yields  between  corporate and Treasury
bonds with similar maturities dropped to ten-year lows.  Manage-ment reduced the
fund's  exposure to corporate  bonds as they became less  attractive in terms of
yield.

             Balanced
         INVESTOR CLASS(1)
Total Returns:         AS OF 4/30/97
  6 Months                  1.94%(2)
  1 Year                      10.24%
Net Assets:             $852 million
  (As of 4/30/97)
Inception Date:             10/20/88
Ticker Symbol:                 TWBIX

(1) See Share Classes, page 21.
(2) Not annualized.


Many of the investment  terms in this report are defined in the Glossary on page
25.


Semiannual Report                                       Report Highlights      1


                               OUR MESSAGE TO YOU

           [photo of James E. Stowers, Jr. and James E. Stowers III]

April 30,  1997,  marked the end of an  eventful  period for our company and the
Balanced   fund.  We  entered  1997  with  a  new   identity--AMERICAN   CENTURY
INVESTMENTS.  American  Century  encompasses  the skills,  talents and resources
brought together when Twentieth Century Mutual Funds and The Benham Group merged
during 1995 and 1996.

Changing the company's name after being known as Twentieth  Century Mutual Funds
for  almost  40 years  was a  significant  step.  Although  our core  investment
disciplines  remain  unchanged,  the combination of Twentieth Century and Benham
allows us to bring you a full menu of  nearly 70 funds.  We've  also  introduced
three new groups for the funds--the  Benham Group (money market and bond funds),
the American Century Group (asset allocation,  balanced, conservative equity and
specialty  funds)  and  the  Twentieth  Century  Group  (aggressive  growth  and
international  equity  funds).  Balanced is part of the American  Century  Group
because its investment  approach--long-term growth with less volatility than our
pure equity growth funds--matches key attributes of that group.

During the past six months,  we also began to offer  multiple  classes of shares
for many funds. These new share classes acknowledge the differences in the types
of investors who invest in our funds and the growing role of financial  advisors
and financial  institutions as a distribution channel for fund shares.  Balanced
now has three share classes--the  Investor Class, designed for investors who buy
directly from American  Century,  the Advisor Class,  designed for investors who
buy through  certain  financial  intermediaries,  and the  Institutional  Class,
although no shares of this class have been sold yet.

Another part of serving  investors is providing  the best  possible  information
regularly in a helpful format. Based on investors' feedback,  we have redesigned
our  shareholder  reports to include  new  features,  such as a one-page  report
summary,  a glossary,  more charts and graphs,  and expanded  Management Q&A and
background information sections. This report displays the new format.

We appreciate your confidence in American Century and look forward to continuing
to serve you.

Sincerely,

/s/James E. Stowers, Jr.                   /s/James E. Stowers III              
James E. Stowers, Jr.                      James E. Stowers III              
Chairman of the Board and Founder          President and Chief Executive Officer
                                        


2    Our Message to You                             American Century Investments


                                PERIOD OVERVIEW

U.S. STOCK MARKET

The six-month period ended April 30, 1997, produced widely divergent returns for
U.S.  stock  investors.  In general,  the shares of large  companies  (large-cap
stocks), particularly relatively stable,  industry-leading firms in the S&P 500,
significantly outperformed the shares of faster-growing, smaller companies (mid-
and small-cap stocks).  Value stocks (shares of companies that are lower priced)
generally   outperformed   growth  stocks  (those  of  companies   demonstrating
above-average  earnings growth) as investors placed a higher premium on earnings
stability than on earnings growth.

The S&P 500 typically  represents the large-cap sector of the U.S. stock market.
Many investors also use the index as a proxy for the U.S. market as a whole. The
sustained  advance  of the S&P 500 was  one of the key  success  stories  of the
period. The index posted a 14.74% total return during the six months, continuing
a  three-year  trend of unusually  strong  large-cap  performance.  Factors that
supported the S&P 500's performance included:

o Investors  seeking  predictable  earnings  and  liquidity  because they feared
rising interest rates and an economic slowdown. The shares of large,  well-known
firms such as Johnson & Johnson and Microsoft rallied appreciably.

o  Favorable   economic   conditions  (robust  growth  and  low  inflation)  and
particularly strong earnings growth for large-cap companies.

o The popularity and success of S&P 500 index funds.  With more investor dollars
chasing  stocks in the S&P 500, the prices of those shares rose much faster than
the prices of mid- and small-cap stocks.


U.S. BOND MARKET

U.S.  bonds  produced  modest  returns  during the  period.  Recent  evidence of
increasing wage pressures--which are often passed on to consumers in the form of
higher  prices--led the Federal  Reserve (the Fed) to make a pre-emptive  strike
against inflation by raising short-term  interest rates in March. The Fed raised
its federal  funds rate target (the  overnight  lending rate  targeted for large
loans  between  commercial  banks) from 5.25% to 5.50%.  Rising  interest  rates
caused  bond prices to fall,  but the  interest  income paid out to  bondholders
offset  the price  declines  for the most  part.  Short-term  securities,  which
usually suffer less price depreciation than longer-term securities when interest
rates are rising,  were the best performers during the period. For example,  the
two-year Treasury note posted a 2.38% return for the six-month period, while the
30-year Treasury bond returned 0.74%.

[line graph - data below]

COMPARATIVE PERFORMANCE (Growth of $1.00)
For the six-month period ended April 30, 1997

             LEHMAN
          INTERMEDIATE
            GOVT/CORP                  BLENDED
           BOND INDEX     S&P 500       INDEX
Oct-96        $1.00        $1.00        $1.00
Nov-96        $1.04        $1.07        $1.05
Dec-96        $1.01        $1.06        $1.04
Jan-97        $1.06        $1.12        $1.08
Feb-97        $1.03        $1.13        $1.08
Mar-97        $0.99        $1.08        $1.05
Apr-97        $1.02        $1.15        $1.10

   S&P 500                             14.74%
   Blended Index                        9.52%
   Lehman Intermediate Govt/Corp
     Bond Index                         1.74%
SOURCE: LIPPER ANALYTICAL SERVICES, INC.


Semiannual Report                                         Period Overview      3


<TABLE>
<CAPTION>
                      PERFORMANCE & PORTFOLIO INFORMATION

TOTAL RETURNS AS OF APRIL 30, 1997
                                                               AVERAGE ANNUAL RETURNS
                                 6 MONTHS       1 YEAR         3 YEARS         5 YEARS     LIFE OF FUND

INVESTOR CLASS (inception 10/20/88)
<S>                                <C>          <C>            <C>              <C>           <C>   
     Balanced                      1.94%        10.24%         11.42%           8.83%         11.71%
     Blended Index                 9.52%        17.64%         17.25%          12.95%        13.19%(1)

ADVISOR CLASS (inception 1/6/97)
     Balanced                                                                                 -0.57%
     Blended Index                                                                           1.72%(2)
</TABLE>

(1)  Return from 10/31/88, the date nearest the class's inception for which data
     are available.

(2)  Return from 1/31/97,  the date nearest the class's inception for which data
     are available.

See pages 21, 24 and 25 for more  information  about share classes,  the Blended
Index and returns.

[line graph - data below]

GROWTH OF $10,000 OVER LIFE OF FUND (Investor Class)

    VALUE ON 4/30/97
Blended Index     $29,863
Balanced $25,940

                                   BLENDED
                  BALANCED          INDEX
10/31/88           $10,000         $10,000
4/30/89            $10,620         $10,872
4/30/90            $12,060         $11,947
4/30/91            $14,585         $13,875
4/30/92            $16,992         $15,643
4/30/93            $17,345         $17,261
4/30/94            $18,747         $17,906
4/30/95            $20,025         $20,333
4/30/96            $23,530         $24,959
4/30/97            $25,940         $29,863

Past  performance  does not  guarantee  future  results.  Investment  return and
principal  value will fluctuate,  and redemption  value may be more or less than
original  cost.  Data quoted is for Investor Class only;  performance  for other
classes will vary due to  differences  in fee  structure  (see the Total Returns
table above).

The line representing  Balanced's total return includes operating expenses (such
as transaction  costs and management fees) that reduce returns,  while the total
return line of the Blended Index does not.

[pie chart]

ASSET ALLOCATION (as of April 30, 1997)
   Common Stocks                          58%
   Corporate Bonds                        23%
   U.S. Treasury Securities                7%
   Mortgage & Asset-Backed Securities      6%
   Other                                   6%


4    Performance & Portfolio Information            American Century Investments


                                MANAGEMENT Q & A

An interview with Bruce Wimberly and Jeff Houston, two of the portfolio managers
on the Balanced management team.

HOW DID THE FUND PERFORM?

For the  six-month  period  ended April 30,  1997,  the fund's  total return was
1.94%,  reflecting  the  combined  performance  of the  fund's  stock  and  bond
portfolios.  Stocks represent  approximately 60% of the fund's assets, while the
remaining  assets are invested in bonds.  Balanced's  mix of stocks and bonds is
designed  to  provide  investors  with a buffer in varying  market and  economic
environments.

Unfortunately,  the fund's small- and mid-cap stock  holdings were out of favor,
as  discussed  in the  Period  Overview  on page 3, and its bond  holdings  also
suffered as interest  rates rose.  For the period,  the fund's  stock  portfolio
returned  1.93%,  compared with 14.74% for the S&P 500, while the bond portfolio
returned 1.48%,  compared to the 1.74% return posted by its benchmark index, the
Lehman Intermediate  Government/Corporate  Bond Index. The fund's benchmark, the
Blended Index,  posted a 9.52% total return for the period.  This index combines
the S&P 500  Index and the  Lehman  Intermediate  Government/Corporate  Index in
proportion to the asset mix of the fund.

WHY DID THE BLENDED INDEX OUTPERFORM THE FUND?

While the performance of the fund's bond portfolio nearly matched the returns of
the  bond  portion  of the  index,  the  fund's  stock  portfolio  significantly
underperformed  the stock  returns  of the  index.  The  benchmark  was  heavily
influenced  by the  exceptionally  strong  performance  of the  S&P  500,  which
represents 60% of the Blended Index. The S&P 500 reflects the performance of the
U.S. stock market generally,  but it has a  large-capitalization  bias.  Company
size was a  significant  factor in stock  performance  during the  period,  with
large-cap  stocks generally  outperforming  mid- and small-cap  companies.  This
market trend worked  against the fund,  since we had purchased  some  attractive
smaller-cap   stocks  late  last  year  in  an  effort  to  improve  the  fund's
performance. We think that blending these smaller, faster-growing companies with
the fund's traditional holdings of

[bar chart - data below]

BALANCED's ONE-YEAR RETURNS OVER THE LIFE OF THE FUND
(Periods ending April 30)

                                   BLENDED
               BALANCED(1)          INDEX
4/89            6.20%(2)          8.72%(2)
4/90              13.56%             9.85%
4/91              20.94%            16.02%
4/92              16.50%            12.62%
4/93               2.08%            10.48%
4/94               8.09%             3.59%
4/95               6.81%            13.07%
4/96              17.51%            21.24%
4/97              10.24%            17.64%

This chart illustrates  Balanced's returns since its inception and compares them
with the Blended Index's  returns.  The fund's total returns  include  operating
expenses, while the index's returns do not. See page 24 for a description of the
index. Past performance is no guarantee of future results.

(1)  Investor  Class (2)  Return  from  10/31/88  (the date  nearest  the fund's
inception date for which data are available) to 4/30/89.


Semiannual Report                                         Period Overview      5


                                MANAGEMENT Q & A

larger,  blue-chip  firms will enhance  returns over time.  This strategy  meant
Balanced  was more  heavily  weighted  in stocks  of  smaller,  more  aggressive
companies  than the S&P 500. The  underperformance  of these stocks,  which were
largely out of favor during the period,  reduced the  performance  of the fund's
stock portfolio below that of its the benchmark. We believe, however, that these
holdings will reward us over time.

WHAT  SPECIFIC  STOCKS OR SECTORS OF THE MARKET HAD THE  GREATEST  IMPACT ON THE
PERFORMANCE OF THE FUND'S STOCK PORTFOLIO?

Some energy-related and technology companies proved disappointing. In the energy
sector,  for  example,  Balanced  was heavily  weighted in the shares of several
oil-drilling  companies,  including  Global  Marine and Falcon  Drilling,  which
demonstrated  impressive growth and whose stock appreciated  steadily during the
previous six months.  We held on to these stocks because we expected to continue
to benefit from  increasing  demand for new oil  supplies.  However,  the stocks
began sliding in mid-January as oil and gas prices fell.

We continue to like technology stocks because of the accelerating  earnings many
of these  companies  produce,  but some  sectors  within  the  technology  group
struggled.  For example,  Balanced's  6% weighting in companies  such as Western
Digital and Applied  Magnetics  Corporation,  which  manufacture disk drives for
computers,  far  exceeded the S&P 500's 1%  weighting  in this  industry.  These
stocks tend to be very volatile in response to fluctuating  levels of supply and
demand.  During the period,  many of these  companies  continued  to show strong
earnings and revenue  growth,  but their  valuations were depressed by skeptical
investors  and  analysts  who did not believe  they could  sustain  their growth
rates.

TOP TEN EQUITY HOLDINGS                % of equity portfolio
                                            As of           As of
                                            4/30/97        10/31/96
Western Digital Corp.                        4.3%             --
Warner-Lambert Co.                           4.1%            1.9%
General Electric Co.                         3.8%            2.9%
Intel Corp.                                  3.8%            4.3%
Johnson & Johnson                            3.6%            3.2%
Pfizer, Inc.                                 3.3%            2.8%
Lilly (Eli) & Co.                            3.1%            2.4%
Merck & Co., Inc.                            3.0%            2.3%
Chase Manhattan Corp.                        2.8%            1.9%
United Technologies Corp.                    2.8%            2.9%


TOP FIVE INDUSTRIES                    % of equity portfolio
                                            As of           As of
                                            4/30/97        10/31/96
Pharmaceuticals                              20.1%           15.9%
Electrical & Electronic Components           12.1%           5.0%
Energy (Production & Marketing)              8.3%            5.6%
Computer Peripherals                         8.2%             --
Diversified Companies                        7.7%            3.6%


WHAT CHANGES ARE YOU MAKING TO THE FUND'S STOCK PORTFOLIO?

We have increased the portfolio's  market  capitalization by adding more quality
mid-cap  stocks,  which still provide a measure of growth while lending  greater
stability to the equity  portion of the  portfolio.  For example,  we have moved
into some high-end,  mid-cap retail names, such as Estee Lauder and Gucci, which
are demonstrating  strong earnings here in the U.S. and abroad.  We're attracted
to these  companies  because they are well managed,  generate a strong cash flow
and are expanding globally.

We've also bought some pharmaceutical  companies,  such as Eli Lilly and Pfizer,
Inc.,  to take  advantage  of a new product  cycle.  Large-scale  investment  in
research  and  development  by drug  companies is starting to result in many new
products  coming to the market.  These new drugs,  combined  with the  favorable
demographic  trends of the aging U.S.  population,  give us confidence that many
companies in this industry should see share price appreciation.

We're reducing our concentrations in several sectors,


6    Performance & Portfolio Information            American Century Investments


                                MANAGEMENT Q & A

such as  energy  and  technology,  to  provide  broader  diversification  in the
portfolio.  By doing so we expect  to  reduce  the  impact  of the  fund's  more
volatile holdings.

HOW WAS THE FUND'S BOND PORTFOLIO POSITIONED DURING THE PERIOD?

The bond portion of the fund  performed  about as well as could be expected in a
period that was not favorable for bonds. We assumed a defensive posture, keeping
the  portfolio's  duration at or below the fund's  neutral level for most of the
period.  The fund's  relatively  short  duration  was a benefit in the  somewhat
volatile  interest rate  environment of the past year.  Rather than try to guess
the  direction of interest  rates,  we took a steady,  conservative  approach to
managing the bond portion of fund.

We also  continued to hold our positions in  mortgage-backed  securities,  which
were the  top-performing  fixed-income  sector for the  period.  Mortgage-backed
securities,  with  their  relatively  high  yields,  tend to  perform  best when
interest  rates are flat or moving within a fairly narrow band, as they were for
most of the period.

HOW HAS THE  LONG-RUNNING  EXPANSION OF THE U.S.  ECONOMY AFFECTED THE CORPORATE
BOND MARKET?

Corporate  bonds  typically offer higher yields than Treasury debt to compensate
investors for their  increased  risk.  The  difference in yields is known as the
"spread." Spreads between  corporate and Treasury bonds with similar  maturities
have fallen to ten-year lows. A vibrant U.S.  economy has fueled this trend; the
strong economy helped to improve corporate balance sheets, which translated into
credit upgrades and higher prices for corporate  debt.  Heavy demand from mutual
fund managers and foreign buyers also helped increase prices and lower yields on
corporate  bonds.  Despite this  improvement in credit  quality,  we reduced our
corporate  exposure during the period because the compression of spreads between
corporate and Treasury securities has made corporate securities  relatively less
attractive.  We've  increased our exposure to  Treasuries.  However,  if spreads
widen, we would likely raise our exposure to corporate debt.

BALANCED'S FIXED-INCOME PORTFOLIO
                                        As of            As of
                                        4/30/97         10/31/96

PORTFOLIO SENSITIVITY TO INTEREST RATES

Weighted Average Maturity             6.28 years        6.1 years
Duration                              4.10 years        3.9 years

PORTFOLIO CREDIT QUALITY  % of fixed income portfolio
     (S&P Ratings)
AAA                                       41%              40%
AA                                        6%               7%
A                                         36%              37%
BBB                                       17%              16%
                                        ------           ------
                                         100%             100%
                                        ======           ======
See Glossary on page 25.


WHAT IS YOUR OUTLOOK FOR THE FUND'S BOND PORTFOLIO?

It is  uncertain  if the Federal  Reserve's  interest  rate hike in March was an
isolated  event or the  first in a series  of  moves.  However,  high  levels of
consumer  confidence,  a robust  housing  market and rising  employment and wage
growth all seem to argue for continued strong U.S. economic progress.  Inflation
has remained  tame, but we are skeptical that prices can remain subdued with the
economy  growing at an annual rate of over 4%. Given that,  we will  continue to
maintain the defensive posture of the fund's bond portfolio.  Rather than try to
guess the Fed's  interest  rate  intentions,  we'll  continue to  conservatively
manage the portfolio's duration and average maturity.


Semiannual Report                                        Management Q & A      7


                            SCHEDULE OF INVESTMENTS

APRIL 30, 1997 (UNAUDITED)

SHARES                ($ IN THOUSANDS)                                 VALUE

COMMON STOCKS
Aerospace & Defense--3.5%
        440,000   BE Aerospace, Inc.(1)                              $10,752
         55,000   Boeing Co.                                           5,424
        180,000   United Technologies Corp.                           13,613
                                                                  ----------
                                                                      29,789
                                                                  ----------
BANKING--4.4%
        105,000   BankAmerica Corp.                                   12,272
        150,000   Chase Manhattan Corp.                               13,894
        100,000   Citicorp                                            11,262
                                                                  ----------
                                                                      37,428
                                                                  ----------
BIOTECHNOLOGY--0.3%
        165,000   Bio-Technology General Corp.(1)                      2,393
                                                                  ----------
BROADCASTING & MEDIA--2.4%
        226,700   Clear Channel Communications, Inc.(1)               10,995
        328,800   Outdoor Systems, Inc.(1)                             9,083
                                                                  ----------
                                                                      20,078
                                                                  ----------
COMPUTER PERIPHERALS--4.8%
        360,000   Applied Magnetics Corp.(1)                           9,045
        400,000   Read-Rite Corp.(1)                                  10,375
        340,000   Western Digital Corp.(1)                            20,952
                                                                  ----------
                                                                      40,372
                                                                  ----------
COMPUTER SOFTWARE & SERVICES--3.6%
        154,600   BMC Software, Inc.(1)                                6,677
        270,000   Compuware Corp.(1)                                  10,192
        300,000   Electronics for Imaging, Inc.(1)                    11,737
         50,000   Oracle Systems Corp.(1)                              1,991
                                                                  ----------
                                                                      30,597
                                                                  ----------
COMPUTER SYSTEMS--2.0%
       140,000    Compaq Computer Corp.(1)                            11,953
       165,000    Sun Microsystems, Inc.(1)                            4,754
                                                                  ----------
                                                                      16,707
                                                                  ----------
CONSUMER PRODUCTS--3.9%
         90,000   Avon Products, Inc.                                  5,546
        150,000   Estee Lauder Companies, Inc.                         6,863
        130,000   Gillette Company                                    11,050
         75,000   Procter & Gamble Co. (The)                           9,431
                                                                  ----------
                                                                      32,890
                                                                  ----------

SHARES                 ($ IN THOUSANDS)                                VALUE

DIVERSIFIED COMPANIES--4.4%
        170,000   General Electric Co.                               $18,849
       135,000    Honeywell Inc.                                       9,534
       100,000    Johnson Controls, Inc.                               3,837
       145,100    U.S. Industries, Inc.(1)                             5,242
                                                                  ----------
                                                                      37,462
                                                                  ----------
ELECTRICAL & ELECTRONIC
COMPONENTS--7.0%
       145,000    Altera Corp.(1)                                      7,187
       120,000    Intel Corp.                                         18,375
       280,000    KLA Instruments Corp.(1)                            12,477
       275,000    LSI Logic Corp.(1)                                  10,519
       200,000    Phillips Electronics N.V.                           10,700
                                                                  ----------
                                                                      59,258
                                                                  ----------
ENERGY (PRODUCTION & MARKETING)--4.8%
        135,000   Diamond Offshore Drilling, Inc.(1)                   8,691
         70,000   Energy Ventures, Inc.(1)                             4,681
        351,300   Falcon Drilling Co. Inc.(1)                         13,437
        425,000   Global Marine Inc.(1)                                8,553
        325,000   Tubos de Acero de Mexico, S.A. ADR(1)                5,322
                                                                  ----------
                                                                      40,684
                                                                  ----------
ENVIRONMENTAL SERVICES--0.3%
         90,000   USA Waste Services, Inc.(1)                          2,948
                                                                  ----------
FINANCIAL SERVICES--0.5%
        100,000   Federal National Mortgage Association                4,113
                                                                  ----------
FOOD & BEVERAGE--0.6%
        175,000   Panamerican Beverages Inc.                           5,075
                                                                  ----------
HEALTHCARE--0.7%
        120,000   Cardinal Health, Inc.                                6,390
                                                                  ----------
INSURANCE--2.3%
        225,000   Conseco Inc.                                         9,309
        230,000   SunAmerica, Inc.                                    10,580
                                                                  ----------
                                                                      19,889
                                                                  ----------
PHARMACEUTICALS--11.6%
        110,000   American Home Products Corp.                         7,288
        290,000   Johnson & Johnson                                   17,763
        170,000   Lilly (Eli) & Co.                                   14,939
        160,000   Merck & Co., Inc.                                   14,480
          5,653   Novartis ORD                                         7,463

See Notes to Financial Statements


8    Schedule of Investments                        American Century Investments


                            SCHEDULE OF INVESTMENTS

APRIL 30, 1997 (UNAUDITED)

SHARES/PRINCIPAL AMOUNT        ($ IN THOUSANDS)                        VALUE

        170,000   Pfizer, Inc.                                       $16,320
        205,000   Warner-Lambert Co.                                  20,090
                                                                  ----------
                                                                      98,343
                                                                  ----------
RETAIL (APPAREL)--0.6%
         75,000   Gucci Group N.V.                                     5,203
                                                                  ----------

TOTAL COMMON STOCKS--57.7%                                           489,619
                                                                  ----------
   (Cost $399,980)

U.S. TREASURY SECURITIES
        $12,350   U.S. Treasury Notes,
                    6.125%, 3/31/98                                   12,377
          5,000   U.S. Treasury Notes,
                    6.00%, 9/30/98                                     4,992
          4,075   U.S. Treasury Notes,
                    7.75%, 2/15/01                                     4,242
          2,000   U.S. Treasury Notes,
                    6.625%, 6/30/01                                    2,005
         12,500   U.S. Treasury Notes,
                    5.75%, 8/15/03                                    11,930
          2,050   U.S. Treasury Notes,
                    5.875%, 2/15/04                                    1,962
          4,000   U.S. Treasury Notes,
                    7.25%, 5/15/04                                     4,125
          5,000   U.S. Treasury Notes,
                    7.25%, 8/15/04                                     5,158
          3,800   U.S. Treasury Notes,
                    7.00%, 7/15/06                                     3,863
          4,300   U.S. Treasury Notes,
                    6.25%, 2/15/07                                     4,159
          6,500   U.S. Treasury Bonds,
                    7.625%, 2/15/25                                    6,961
                                                                  ----------

TOTAL U.S. TREASURY SECURITIES--7.3%                                  61,774
                                                                  ----------
   (Cost $62,364)

MORTGAGE-BACKED SECURITIES(2)
            239   FHLMC Series 1239--
                    EPAC REMIC, 6.80%, 1/15/16                           239
            909   FHLMC Series 106--
                    EPAC REMIC, 6.95%, 12/15/20                          908
          2,000   FHLMC Series 77--
                    HPAC REMIC, 8.50%, 9/15/20                         2,113
          7,489   FNMA Pool #050985,
                    6.00%, 3/1/00                                      7,191

PRINCIPAL AMOUNT           ($ IN THOUSANDS)                            VALUE

         $  387   FNMA 89 Series 85--
                    DPAC REMIC, 7.60%, 5/25/18                          $388
          1,597   FNMA 90 Series 98--
                    HPAC REMIC, 7.50%, 10/25/19                        1,600
          8,151   FNMA Pool #250627,
                    8.00%, 7/1/26                                      8,283
          7,291   GNMA Pool #002202,
                    7.00%, 4/20/26                                     7,042
                                                                  ----------

TOTAL MORTGAGE-BACKED SECURITIES--3.3%                                27,764
                                                                  ----------
   (Cost $27,876)

ASSET-BACKED SECURITIES(2)
          3,750   FNMA Whole Loan, Series 1995-W1,
                    Class A6, 8.10%, 4/25/25                           3,862
          5,000   First Merchants Auto Receivables
                    Corp., Series 1996-B, Class A2,
                    6.80%, 5/15/01                                     5,038
          5,000   NationsBank Auto Owner Trust,
                    Series 1996-A, Class B1,
                    6.75%, 6/15/01                                     5,029
          5,000   Premier Auto Trust, Series 1996-4,
                    Class CTFS, 6.65%, 8/6/02                          4,966
          3,000   Union Acceptance Corp., Series
                    1996-D, Class A3, 6.30%, 1/8/04                    2,944
          4,350   United Companies Financial Corp.,
                    Series 1996-D1, Class A4,
                    6.776%, 2/15/16                                    4,298
                                                                  ----------
TOTAL ASSET-BACKED SECURITIES--3.1%                                   26,137
                                                                  ----------
   (Cost $26,133)

CORPORATE BONDS
AUTOMOBILES & AUTO PARTS--2.1%
          6,500   Ford Motor Credit Corp.,
                    6.75%, 5/15/05                                     6,289
          7,000   General Motors Acceptance Corp.,
                    MTN, 6.375%, 10/12/99                              6,974
          5,000   General Motors Acceptance Corp.,
                    MTN, 5.45%, 2/22/00                                4,831
                                                                  ----------
                                                                      18,094
                                                                  ----------
BANKING--4.3%
          4,000   Capital One Financial Corp.,
                    8.125%, 3/1/00                                     4,100

See Notes to Financial Statements


Semiannual Report                                 Schedule of Investments      9


                            SCHEDULE OF INVESTMENTS

APRIL 30, 1997 (UNAUDITED)

PRINCIPAL AMOUNT             ($ IN THOUSANDS)                          VALUE

         $2,000   Citicorp, MTN, 7.125%, 9/1/05                       $1,987
          5,000   First Union Corp., 8.77%, 11/15/04                   5,219
          1,200   MBNA Corp., 6.875%, 6/1/05                           1,159
          4,730   National Bank of Canada, 8.125%,
                    8/15/04                                            4,961
          5,150   NationsBank Capital Trust III,
                    VRN, 6.37%, 1/15/07,  resets 
                    quarterly off the 3-month LIBOR
                    plus 0.55% with no caps, final
                    maturity 1/15/27                                  5,013
          4,000   National Westminster Bank PLC, VRN,
                    7.75%, 10/16/07, resets semi-
                    annually off the 6-month LIBOR
                    plus 1.45% with no caps, final
                    maturity 4/29/49                                   4,050
          5,000   NationsBank Corp., 6.875%, 2/15/05                   4,881
          5,150   Santander Financial Issuances Ltd.,
                    7.00%, 4/1/06                                      5,041
                                                                  ----------
                                                                      36,411
                                                                  ----------
COMMUNICATIONS SERVICES--1.4%
          3,000   GTE South, 7.25%, 8/1/02                             3,045
          1,500   Tele-Communications, Inc., 8.25%,
                    1/15/03                                            1,523
          7,000   WorldCom, Inc., 7.75%, 4/1/07                        6,991
                                                                  ----------
                                                                      11,559
                                                                  ----------
DIVERSIFIED COMPANIES--0.6%
          5,000   Hanson Overseas BV, 6.75%,
                    9/15/05                                            4,831
                                                                  ----------
FINANCIAL SERVICES--5.4%
          4,000   Associates First Capital Corp.,
                    6.75%, 7/15/01                                     3,980
          2,000   Comdisco, Inc., 6.375%, 11/30/01                     1,947
          5,000   Deutsche Bank AG, 6.70%,
                    12/13/06                                           4,800
          5,000   First USA, Inc., 7.00%, 8/20/01                      4,975
          3,000   Greyhound Financial Corp., 6.75%,
                    3/25/99                                            3,011
          3,000   Lehman Brothers, Inc., 5.75%,
                    11/15/98                                           2,970
          6,000   Lehman Brothers Holdings, Inc.,
                    6.625%, 11/15/00                                   5,940
          3,000   Money Store Inc. (The), 8.05%,
                    4/15/02                                            3,030

PRINCIPAL AMOUNT           ($ IN THOUSANDS)                            VALUE

         $6,000   Norwest Financial, Inc., 6.25%,
                    11/1/02                                           $5,850
          4,750   Salomon Brothers Inc., 6.50%,
                    3/1/00                                             4,697
          5,000   Travelers/Aetna Property Casualty
                    Corp., 6.75%, 4/15/01                              4,969
                                                                  ----------
                                                                      46,169
                                                                  ----------
INDUSTRIAL EQUIPMENT & MACHINERY--0.5%
          4,750   Anixter International Inc., 8.00%,
                    9/15/03                                            4,792
                                                                  ----------
INSURANCE--1.6%
          5,000   Aetna Services Inc., 6.75%,
                    8/15/01                                            4,975
          3,750   Nationwide Mutual Insurance Co.,
                    6.50%, 2/15/04
                    (Acquired 2/9/96, Cost $3,781)(3)                  3,581
          5,000   Underwriters Reinsurance Co.,
                    7.875%, 6/30/06
                    (Acquired 8/6/96, Cost $5,156)(3)                  5,119
                                                                  ----------
                                                                      13,675
                                                                  ----------
PUBLISHING--0.7%
          5,750   Time Warner Inc., 8.11%, 8/15/06                     5,872
                                                                  ----------
REAL ESTATE--1.4%
          6,800   Price REIT, Inc. (The), 7.25%,
                    11/1/00                                            6,792
          5,000   Spieker Properties, Inc., 6.80%,
                    12/15/01                                           4,937
                                                                  ----------
                                                                      11,729
                                                                  ----------
RETAIL (GENERAL MERCHANDISE)--0.9%
          2,500   Dayton Hudson Corp., 9.25%,
                    3/1/06                                             2,669
          4,500   Sears, Roebuck & Co., MTN, 8.23%,
                    10/21/04                                           4,770
                                                                  ----------
                                                                       7,439
                                                                  ----------
TOBACCO PRODUCTS--1.7%
          6,550   Philip Morris Companies Inc., 6.80%,
                    12/1/03                                            6,370
          5,500   Philip Morris Companies Inc., 6.95%,
                    6/1/06                                             5,493
          2,175   RJR Nabisco, Inc., 8.75%, 4/15/04                    2,213
                                                                  ----------
                                                                      14,076
                                                                  ----------

See Notes to Financial Statements


10   Schedule of Investments                        American Century Investments


                            SCHEDULE OF INVESTMENTS

APRIL 30, 1997 (UNAUDITED)

PRINCIPAL AMOUNT          ($ IN THOUSANDS)                             VALUE

UTILITIES--1.9%
         $6,750   China Light & Power Co. Ltd., 7.50%,
                    4/15/06                                           $6,758
          2,000   Kansas Power & Light Co., 8.875%,
                    3/1/00                                             2,097
          5,600   Public Service Electric & Gas Co.,
                    6.00%, 5/1/00                                      5,474
          2,000   Texas Utilities Electric Co., 8.125%,
                    2/1/02                                             2,087
                                                                  ----------
                                                                      16,416
                                                                  ----------
TOTAL CORPORATE BONDS--22.5%                                         191,063
                                                                  ----------
   (Cost $188,339)

SOVEREIGN GOVERNMENTS & AGENCIES
          6,000   Hydro-Quebec, MTN, 7.02%,
                    3/23/05                                            5,917
          4,125   Korea Development Bank, 6.50%,
                    11/15/02                                           4,001
          5,000   Korea Electric Power, 6.375%,
                    12/1/03                                            4,813
                                                                  ----------

TOTAL SOVEREIGN GOVERNMENTS
& Agencies--1.7%                                                      14,731
                                                                  ----------
   (Cost $18,692)

TEMPORARY CASH INVESTMENTS(4)
         $18,700 par value FHLB Discount Note,
         5.34%, 5/1/97                                                18,700

         Repurchase Agreement, J.P. Morgan Securities,
         Inc., (U.S. Treasury obligations), in a joint
         trading account at 5.375%, dated 4/30/97,
         due 5/1/97 (Delivery value $18,303)                          18,300
                                                                  ----------

TOTAL TEMPORARY CASH INVESTMENTS--4.4%                                37,000
                                                                  ----------
   (Cost $37,000)

TOTAL INVESTMENT SECURITIES--100.0%                                 $848,088
                                                                  ==========
   (Cost $760,384)


FORWARD FOREIGN CURRENCY CONTRACTS

      Contract         Settlement                    Unrealized
       to Sell            Date           Value          Gain
     ----------------- -------------- ------------ -------------
      8,524,724  CHF     6/30/97        $5,834           $15
                                      ============ =============
(Value on Settlement Date $5,849)

NOTES TO SCHEDULE OF INVESTMENTS

ADR = American Depositary Receipt

CHF = Swiss Franc

FHLB = Federal Home Loan Bank

FHLMC = Federal Home Loan Mortgage Corporation

FNMA = Federal National Mortgage Association

GNMA = Government National Mortgage Association

LIBOR = London Interbank Offered Rate

MTN = Medium Term Note

Resets = The frequency  with which a  fixed-income  security's  coupon  changes,
based on current market conditions or an underlying index. The more frequently a
security resets,  the less risk the investor is taking that the coupon will vary
significantly from current market rates.

ORD = Foreign Ordinary Share

VRN =  Variable  Rate  Note.  Interest  reset  date  is  indicated  and  used in
calculating the weighted  average  portfolio  maturity.  Rate shown is effective
April 30, 1997.

(1)  Non-income producing.

(2) Final maturity  indicated.  Expected remaining maturity used for purposes of
calculating the weighted average portfolio maturity.

(3) Security was purchased  under Rule 144A of the  Securities  Act of 1933 and,
unless registered under the Act or exempted from registration,  may only be sold
to  qualified  institutional   investors.  The  aggregate  value  of  restricted
securities at April 30, 1997,  was  $8,700,000,  which  represented  1.0% of net
assets.

(4) The  rates  for U.S.  Government  Agency  discount  notes  are the  yield to
maturity at April 30, 1997.

See Notes to Financial Statements


Semiannual Report                                 Schedule of Investments     11


                      STATEMENT OF ASSETS AND LIABILITIES

APRIL 30, 1997 (UNAUDITED)

ASSETS                         ($ in Thousands Except for Per-Share Amounts)

Investment securities, at value
     (identified cost of $760,384) (Note 3) ...................     $848,088
Cash ..........................................................          178
Receivable for forward foreign currency contract ..............           15
Receivable for investments sold ...............................       14,216
Receivable for capital shares sold ............................          213
Dividends and interest receivable .............................        5,088
                                                                ------------
                                                                     867,798
                                                                ------------

LIABILITIES

Disbursements in excess of demand deposit cash ................        1,546
Payable for investments purchased .............................        6,910
Payable for capital shares redeemed ...........................        3,507
Accrued management fees (Note 2) ..............................          692
Distribution fees payable (Note 2) ............................            1
Service fees payable (Note 2) .................................            1
Other liabilities .............................................            3
                                                                ------------
                                                                      12,660
                                                                ------------
Net Assets ....................................................     $855,138
                                                                ============

NET ASSETS CONSIST OF:

Capital (par value and paid in surplus) .......................     $724,392
Undistributed net investment income ...........................        1,870
Accumulated net realized gain on investment
     and foreign currency transactions ........................       41,160
Net unrealized appreciation on investments
     and translation of assets and
     liabilities in foreign currencies (Note 3) ...............       87,716
                                                                ------------
                                                                    $855,138
                                                                ============
INVESTOR CLASS ($ AND SHARES IN FULL)
Net assets .................................................... $851,652,189
Shares outstanding ............................................   49,194,260
Net asset value per share .....................................       $17.31

ADVISOR CLASS ($ AND SHARES IN FULL)
Net assets ....................................................   $3,486,144
Shares outstanding ............................................      201,464
Net asset value per share .....................................       $17.30

See Notes to Financial Statements


12   Statement of Assets and Liabilities            American Century Investments


                            STATEMENT OF OPERATIONS

FOR THE SIX MONTHS ENDED APRIL 30, 1997 (UNAUDITED)

INVESTMENT INCOME                                           ($ in Thousands)

INCOME:
Interest ........................................................    $11,941
Dividends (net of foreign taxes withheld of $21) ................      2,087
                                                                  ----------
                                                                      14,028
                                                                  ----------
EXPENSES (NOTE 2):
Management fees .................................................      4,358
Distribution fees--Advisor Class ................................          2
Shareholder service fees--Advisor Class .........................          2
Directors' fees and expenses ....................................          6
                                                                  ----------
                                                                       4,368
                                                                  ----------

NET INVESTMENT INCOME ...........................................      9,660
                                                                  ----------

REALIZED AND UNREALIZED GAIN (LOSS)
ON INVESTMENTS AND FOREIGN CURRENCY (NOTE 3)

NET REALIZED GAIN ON:
Investments .....................................................     40,539
Foreign currency transactions ...................................        794
                                                                  ----------
                                                                      41,333
                                                                  ----------

Change in net unrealized appreciation (depreciation) on:
Investments .....................................................   (33,742)
Translation of assets and liabilities in foreign currencies .....         13
                                                                  ----------
                                                                    (33,729)
                                                                  ----------

NET REALIZED AND UNREALIZED
GAIN ON INVESTMENTS .............................................      7,604
                                                                  ----------

NET INCREASE IN NET ASSETS
RESULTING FROM OPERATIONS .......................................    $17,264
                                                                  ==========

See Notes to Financial Statements


Semiannual Report                                 Statement of Operations     13


                      STATEMENTS OF CHANGES IN NET ASSETS

SIX MONTHS ENDED APRIL 30, 1997 (UNAUDITED)
AND YEAR ENDED OCTOBER 31, 1996

INCREASE (DECREASE) IN NET ASSETS                        1997             1996

OPERATIONS                                                    ($ in Thousands)

Net investment income ..............................   $9,660          $21,381
Net realized gain on investments
     and foreign currency transactions .............   41,333           66,241
Change in net unrealized appreciation
     (depreciation) on investments and
     translation of assets and liabilities
     in foreign currencies ......................... (33,729)           24,176
                                                   ----------       ----------
Net increase in net assets resulting
     from operations ...............................   17,264          111,798
                                                   ----------       ----------


DISTRIBUTIONS TO SHAREHOLDERS

From net investment income:
     Investor Class ................................ (10,691)         (21,812)
     Advisor Class .................................     (11)              --
From net realized gains from investment transactions:

     Investor Class ................................ (64,787)         (46,792)

     Advisor Class .................................      --                --
                                                   ----------       ----------

Decrease in net assets from distributions .......... (75,489)         (68,604)
                                                   ----------       ----------

CAPITAL SHARE TRANSACTIONS (NOTE 4)

Net increase in net assets from capital
     share transactions ............................   34,195           20,404
                                                   ----------       ----------

NET INCREASE (DECREASE) IN NET ASSETS .............. (24,030)           63,598

NET ASSETS

Beginning of period ................................  879,168          815,570
                                                   ----------       ----------

End of period ...................................... $855,138         $879,168
                                                   ==========       ==========

Undistributed net investment income ................   $1,870           $2,912
                                                   ==========       ==========

See Notes to Financial Statements


14   Statements of Changes in Net Assets            American Century Investments


                         NOTES TO FINANCIAL STATEMENTS

APRIL 30, 1997 (UNAUDITED)

1. ORGANIZATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

ORGANIZATION---American   Century  Mutual  Funds,   Inc.  (the  Corporation)  is
registered under the Investment  Company Act of 1940 as an open-end  diversified
management investment company.  American Century Balanced Fund (the Fund) is one
of the  seventeen  series  of  funds  issued  by  the  Corporation.  The  Fund's
investment  objective  is to seek  capital  growth  and  current  income.  It is
management's  intention to maintain  approximately  60% of the Fund's  assets in
common stocks and the remainder in bonds and other fixed income  securities.  On
September 3, 1996, the Fund  implemented a multiple class structure  whereby the
Fund is  authorized to issue three classes of shares:  the Investor  Class,  the
Advisor Class,  and the  Institutional  Class. The shares  outstanding  prior to
September 3, 1996, were  designated as Investor Class shares.  The three classes
of shares  differ  principally  in their  respective  shareholder  servicing and
distribution  expenses  and  arrangements.  All shares of the Fund  represent an
equal pro rata interest in the assets of the class to which such shares  belong,
and have identical voting,  dividend,  liquidation and other rights and the same
terms and conditions, except for class specific expenses and exclusive rights to
vote on matters  affecting only  individual  classes.  Sale of the Advisor Class
commenced on January 6, 1997. Sale of the Institutional  Class had not commenced
as of April 30, 1997. The following  significant  accounting policies related to
the Fund are in accordance with accounting  policies  generally  accepted in the
investment company industry.

SECURITY  VALUATIONS---Portfolio  securities  traded  primarily  on a  principal
securities  exchange are valued at the last reported sales price, or the mean of
the  latest  bid and  asked  prices  where no last  sales  price  is  available.
Securities traded  over-the-counter are valued at the mean of the latest bid and
asked prices or, in the case of certain foreign securities, at the last reported
sales price,  depending on local  convention or regulation.  Debt securities not
traded on a principal securities exchange are valued through valuations obtained
from a  commercial  pricing  service  or at the mean of the most  recent bid and
asked prices.  When valuations are not readily available,  securities are valued
at fair value as determined in accordance with  procedures  adopted by the Board
of Directors.

SECURITY  TRANSACTIONS---Security  transactions  are  accounted  for on the date
purchased  or  sold.  Net  realized  gains  and  losses  are  determined  on the
identified cost basis, which is also used for federal income tax purposes.

INVESTMENT  INCOME---Dividend  income less  foreign  taxes  withheld (if any) is
recorded as of the ex-dividend date.  Interest income is recorded on the accrual
basis and includes amortization of discounts and premiums.

FOREIGN  CURRENCY   TRANSACTIONS---The   accounting  records  of  the  Fund  are
maintained in U.S. dollars.  All assets and liabilities  initially  expressed in
foreign currencies are converted into U.S. dollars at prevailing exchange rates.
Purchases and sales of investment securities,  dividend and interest income, and
certain  expenses  are  translated  at the rates of exchange  prevailing  on the
respective dates of such transactions.

Net  realized  foreign  currency  exchange  gains or losses  arise from sales of
foreign  currencies  and the  difference  between  asset and  liability  amounts
initially stated in foreign  currencies and the U.S. dollar value of the amounts
actually  received or paid. Net unrealized  foreign  currency  exchange gains or
losses  arise from  changes in the value of assets and  liabilities,  other than
portfolio securities, resulting from changes in the exchange rates.

Net realized and unrealized  foreign currency exchange gains or losses occurring
during the holding  period of portfolio  securities  are a component of realized
gain  (loss)  on  investments  and  unrealized  appreciation  (depreciation)  on
investments, respectively.

FORWARD FOREIGN CURRENCY  EXCHANGE  CONTRACTS---The  Fund may enter into forward
foreign  currency  exchange  contracts  for the  purpose  of  settling  specific
purchases or sales of securities  denominated in a foreign  currency or to hedge
the Fund's  exposure  to  foreign  currency  exchange  rate  fluctuations.  When
required,  the Fund will segregate  assets in an amount  sufficient to cover its
obligations  under the hedge  contracts.  The net U.S.  dollar  value of foreign
currency  underlying  all  contractual  commitments  held  by the  Fund  and the
resulting  unrealized  appreciation or depreciation  are determined  daily using
prevailing exchange rates.  Forward contracts involve elements of risk in excess
of the amount  reflected in the  Statement of Assets and  Liabilities.  The Fund
bears the risk of an unfavorable  change in the foreign  currency  exchange rate
underlying  the  forward  contract.  Additionally,   losses  may  arise  if  the
counterparties do not perform under the contract terms.

REPURCHASE  AGREEMENTS---The  Fund may enter  into  repurchase  agreements  with
institutions  the  Fund's  investment   manager,   American  Century  Investment
Management,  Inc. (ACIM),  has determined are creditworthy  pursuant to criteria
adopted by the Board of  Directors.  Each  repurchase  agreement  is recorded at
cost.  The  Fund  requires  that  the  securities   purchased  in  a  repurchase
transaction be transferred to the custodian in a manner sufficient to enable the
Fund to obtain those  securities in the event of a default under the  repurchase
agreement.  ACIM  monitors,  on a  daily  basis,  the  value  of the  securities
transferred  to  ensure  that the  value,  including  accrued  interest,  of the
securities  under each repurchase  agreement is equal to or greater than amounts
owed to the Fund under each repurchase agreement.


Semiannual Report                           Notes to Financial Statements     15


                         NOTES TO FINANCIAL STATEMENTS

APRIL 30, 1997 (UNAUDITED)

JOINT TRADING  ACCOUNT--Pursuant  to an Exemptive Order issued by the Securities
and  Exchange  Commission,  the Fund,  along  with other  registered  investment
companies  having   management   agreements  with  ACIM  and  Benham  Management
Corporation, may transfer uninvested cash balances into a joint trading account.
These  balances  are  invested  in one or more  repurchase  agreements  that are
collateralized by U.S. Treasury or Agency obligations.

INCOME TAX  STATUS---It  is the  policy of the Fund to  distribute  all  taxable
income and capital gains to shareholders and to otherwise qualify as a regulated
investment  company under provisions of the Internal Revenue Code.  Accordingly,
no provision has been made for federal income taxes.

DISTRIBUTIONS  TO  SHAREHOLDERS---Distributions  to shareholders are recorded on
the ex-dividend date.  Distributions from net investment income are declared and
paid  quarterly.  Distributions  from net  realized  gains are declared and paid
annually.

The character of distributions  made during the year from net investment  income
or net  realized  gains may differ  from  their  ultimate  characterization  for
federal  income tax purposes.  These  differences  are due to differences in the
recognition  of  income  and  expense  items  for  financial  statement  and tax
purposes.

SUPPLEMENTARY  INFORMATION---Certain  officers and directors of the  Corporation
are also officers and/or directors, and, as a group, controlling stockholders of
American Century  Companies,  Inc., the parent of the  Corporation's  investment
manager,  ACIM,  the  Corporation's  distributor,  American  Century  Investment
Services,  Inc., ACIS, and the  Corporation's  transfer agent,  American Century
Services Corporation.

USE OF  ESTIMATES---The  preparation of financial  statements in conformity with
generally accepted  accounting  principles requires management to make estimates
and assumptions  that affect the reported  amounts of assets and liabilities and
disclosure of  contingent  assets and  liabilities  at the date of the financial
statements,  and the reported  amounts of increases  and decreases in net assets
from operations  during the reporting  period.  Actual results could differ from
those estimates.

- --------------------------------------------------------------------------------
2. TRANSACTIONS WITH RELATED PARTIES

The Corporation has entered into a Management  Agreement with ACIM that provides
the Fund with  investment  advisory  and  management  services in exchange for a
single,  unified management fee per class.  Additional fees apply to the Advisor
Class, as described in the respective  prospectus.  The Agreement  provides that
all  expenses  of the  Fund,  except  brokerage  commissions,  taxes,  interest,
expenses  of those  directors  who are not  considered  "interested  persons" as
defined in the  Investment  Company  Act of 1940  (including  counsel  fees) and
extraordinary expenses, will be paid by ACIM. The fee is computed daily and paid
monthly based on the Fund's average daily closing net assets during the previous
month.  The annual  management fee is 1.00% for the Investor Class and 0.75% for
the Advisor Class.

The Board of Directors has adopted a shareholder  services and distribution plan
for the Advisor Class,  pursuant to Rule 12b-1 of the Investment  Company Act of
1940.  The Advisor  Class Master  Distribution  and  Shareholder  Services  Plan
provides that the Fund will pay ACIM an annual  distribution  fee equal to 0.25%
and service fee equal to 0.25%.  The fees are  computed  daily and paid  monthly
based on the  Advisor  Class's  average  daily  closing  net  assets  during the
previous month.  The  distribution  fee provides  compensation  for distribution
expenses  incurred in connection with  distributing  shares of the Advisor Class
including,  but not limited to,  payments to  brokers,  dealers,  and  financial
institutions  that have entered into sales agreements with ACIS and/or ACIM. The
service fee provides  compensation for shareholder and  administrative  services
rendered by ACIM,  its  affiliates or independent  third party  providers.  Fees
incurred under the Master Distribution and Shareholder  Services Plan during the
six months ended April 30, 1997, were $4,510.


16   Notes to Financial Statements                  American Century Investments


                         NOTES TO FINANCIAL STATEMENTS

APRIL 30, 1997 (UNAUDITED)

3. INVESTMENT TRANSACTIONS

The aggregate  cost of investment  securities  purchased  (excluding  short-term
investments) for the six months ended April 30, 1997,  totaled  $372,853,132 for
common  stocks,  $71,476,450  for U.S.  Treasury  and  Agency  obligations,  and
$85,758,513 for other debt obligations. Proceeds from investment securities sold
(excluding  short-term  investments)  totaled  $402,686,136  for common  stocks,
$99,215,532 for U.S. Treasury and Agency obligations,  and $70,735,044 for other
debt obligations.

As of April 30, 1997,  accumulated net unrealized  appreciation for Balanced was
$87,559,121,  based on the aggregate  cost of investments  of  $760,528,603  for
federal income tax purposes.  Accumulated net unrealized  appreciation consisted
of unrealized  appreciation  of  $101,305,968  and  unrealized  depreciation  of
$13,746,847.

- --------------------------------------------------------------------------------
4. Capital Share Transactions

There are 100,000,000  shares of the Investor Class and 50,000,000 shares of the
Advisor Class authorized for issuance. All shares are $0.01 par value.
Transactions in shares of the Fund were as follows:

                                    BALANCED
                                                   Shares            Amount

INVESTOR CLASS                                          (In Thousands)

SIX MONTHS ENDED APRIL 30, 1997:
Sold ...........................................     7,549          $134,277
Issued in reinvestment of distributions ........     4,253            74,226
Redeemed .......................................  (10,012)         (177,847)
                                                ----------        ----------
Net increase ...................................     1,790           $30,656
                                                ==========        ==========

YEAR ENDED OCTOBER 31, 1996:
Sold ...........................................    11,553          $202,311
Issued in reinvestment of distributions ........     3,994            67,547
Redeemed .......................................  (14,226)         (249,454)
                                                ----------        ----------
Net increase ...................................     1,321           $20,404
                                                ==========        ==========

ADVISOR CLASS

JANUARY 6, 1997(1) THROUGH APRIL 30, 1997:
Sold ...........................................       203            $3,556
Issued in reinvestment of distributions ........         1                11
Redeemed .......................................       (2)              (28)
                                                ----------        ----------
Net increase ...................................       202            $3,539
                                                ==========        ==========

(1)  Commencement of sale of the Advisor Class.


Semiannual Report                           Notes to Financial Statements     17


                         NOTES TO FINANCIAL STATEMENTS

APRIL 30, 1997 (UNAUDITED)

- --------------------------------------------------------------------------------
5. CORPORATE EVENTS

The following name changes became effective January 1, 1997:
<TABLE>
                     NEW NAMES                                           FORMER NAMES
                     --------------------------------------------------------------------------------------
<S>                 <C>                                                  <C> 
FUNDS' ISSUER:       American Century Mutual Funds, Inc.                 Twentieth Century Investors, Inc.
FUND:                American Century Balanced Fund                      Balanced Investors
PARENT COMPANY:      American Century Companies, Inc.                    Twentieth Century Companies, Inc.
DISTRIBUTOR:         American Century Investment Services, Inc.          Twentieth Century Securities, Inc.
TRANSFER AGENT:      American Century Services Corporation               Twentieth Century Services, Inc.
</TABLE>

18   Notes to Financial Statements                  American Century Investments

<TABLE>
<CAPTION>
                              FINANCIAL HIGHLIGHTS
                                 INVESTOR CLASS

                                                     For a Share Outstanding Throughout the Years Ended October 31 (except as noted)

                                                                   1997(1)        1996       1995       1994       1993       1992

PER-SHARE DATA
<S>                                                                 <C>         <C>        <C>       <C>         <C>        <C>   
Net Asset Value, Beginning of Period ...........................    $18.55      $17.70     $15.94    $16.52      $14.89     $15.11
                                                                 ---------    --------   --------   --------    -------    -------
Income From Investment Operations
     Net Investment Income .....................................   0.20(2)     0.44(2)    0.48(2)       0.42       0.38       0.33
     Net Realized and Unrealized Gain (Loss)
     on Investment Transactions ................................      0.16        1.88       2.03     (0.58)       1.62     (0.23)
                                                                 ---------    --------   --------   --------    -------    -------
     Total From Investment Operations ..........................      0.36        2.32       2.51     (0.16)       2.00       0.10
                                                                 ---------    --------   --------   --------    -------    -------
Distributions
     From Net Investment Income ................................    (0.22)      (0.46)     (0.48)     (0.42)     (0.37)     (0.32)
     From Net Realized Gains on Investment Transactions ........    (1.38)      (1.01)     (0.27)         --         --         --
                                                                 ---------    --------   --------   --------    -------    -------
     Total Distributions .......................................    (1.60)      (1.47)     (0.75)     (0.42)     (0.37)     (0.32)
                                                                 ---------    --------   --------   --------    -------    -------
Net Asset Value, End of Period .................................    $17.31      $18.55     $17.70     $15.94     $16.52     $14.89
                                                                 =========    ========   ========   ========    =======    =======
     Total Return(3) ...........................................     1.94%      14.04%     16.36%    (0.93)%     13.64%      0.63%

RATIOS/SUPPLEMENTAL DATA

Ratio of Operating Expenses to Average Net Assets ..............  1.00%(4)       0.99%      0.98%      1.00%      1.00%      1.00%
Ratio of Net Investment Income to Average Net Assets ...........  2.22%(4)       2.50%      2.90%      2.70%      2.40%      2.40%
Portfolio Turnover Rate ........................................       63%        130%        85%        94%        95%       100%
Average Commission Paid per Investment Security Traded .........   $0.0352     $0.0400    $0.0390      --(5)      --(5)      --(5)
Net Assets, End of Period (in millions) ........................      $852        $879       $816       $704       $706       $654
</TABLE>
(1)  Six months ended April 30, 1997 (unaudited).
(2)  Computed using average shares outstanding throughout the period.
(3)  Total return assumes reinvestment of dividends and capital gains
     distributions, if any. Total returns for periods less than one year
     are not annualized.
(4)  Annualized.
(5)  Disclosure of average commission paid per investment security traded was
     not required prior to the year ended October 31, 1995.

See Notes to Financial Statements


Semiannual Report                                    Financial Highlights     19


                              FINANCIAL HIGHLIGHTS
                                 ADVISOR CLASS

For a Share Outstanding Throughout the Period Indicated

                                                                      1997(1)

PER-SHARE DATA

Net Asset Value, Beginning of Period ...............................   $17.46
                                                                    ---------
Income From Investment Operations
     Net Investment Income .........................................  0.11(2)
     Net Realized and Unrealized Loss
     on Investment Transactions ....................................   (0.21)
                                                                    ---------
     Total From Investment Operations ..............................   (0.10)
                                                                    ---------
Distributions
     From Net Investment Income ....................................   (0.06)
                                                                    ---------
Net Asset Value, End of Period .....................................   $17.30
                                                                    =========
     Total Return(3) ...............................................  (0.57)%

RATIOS/SUPPLEMENTAL DATA

Ratio of Operating Expenses to Average Net Assets .................. 1.25%(4)
Ratio of Net Investment Income to Average Net Assets ............... 1.99%(4)
Portfolio Turnover Rate ............................................      63%
Average Commission Paid per Investment Security Traded .............  $0.0352
Net Assets, End of Period (in thousands) ...........................   $3,486

(1)  January 6, 1997  (commencement  of sale of Advisor Class) through April 30,
     1997 (unaudited).

(2)  Computed using average shares outstanding throughout the period.

(3)  Total  return   assumes   reinvestment   of  dividends  and  capital  gains
     distributions, if any. Total returns for periods less than one year are not
     annualized.

(4)  Annualized.

See Notes to Financial Statements


20   Financial Highlights                           American Century Investments


                           SHARE CLASS AND RETIREMENT
                              ACCOUNT INFORMATION

SHARE CLASSES

Until September 3, 1996,  Balanced  issued one class of fund shares,  reflecting
the fact that most investors bought their shares directly from American Century.
All investors  paid the same annual  unified  management fee and did not pay any
commissions or other fees to purchase shares from American Century.

But increasing numbers of investors are purchasing fund shares through financial
intermediaries who are ordinarily  compensated for the additional  services they
provide.  In September,  American Century began to offer three classes of shares
for  Balanced.  One class is for  investors who still buy directly from American
Century, one is for investors who buy through financial intermediaries,  and the
third class is for large institutional  customers and others who invest at least
$5 million  in an  American  Century  fund or at least $10  million in  multiple
funds.

The original class of Balanced shares is called the Investor  Class.  All shares
issued and  outstanding  before  September  3,  1996,  have been  designated  as
Investor  Class  shares.  Investor  Class  shares  may also be  purchased  after
September 3, 1996.  Investor Class  shareholders  do not pay any  commissions or
other fees for purchase of fund shares directly from American Century. Investors
who buy Investor Class shares through a broker-dealer may be required to pay the
broker-dealer a transaction fee. THE PRICE AND PERFORMANCE OF THE INVESTOR CLASS
SHARES ARE LISTED IN NEWSPAPERS. NO OTHER CLASS IS CURRENTLY LISTED.

In  addition,   there  is  an  ADVISOR  CLASS,  which  is  sold  through  banks,
broker-dealers, insurance companies and financial advisors. Advisor Class shares
are subject to a 0.50% Rule 12b-1 service and distribution fee. Half of that fee
is available to pay for recordkeeping and administrative  services,  and half is
available  to  pay  for   distribution   services   provided  by  the  financial
intermediary  through  which the Advisor Class shares are  purchased.  The total
expense  ratio of the Advisor Class is 0.25% higher than the total expense ratio
of the Investor Class.

The third  class,  the  Institutional  Class,  had not been sold as of April 30,
1997.

All classes of shares  represent a pro rata  interest in the funds and generally
have the same rights and preferences.

RETIREMENT ACCOUNT INFORMATION

As required by law, any distributions you receive from an IRA and certain 403(b)
distributions  [not  eligible for  rollover to an IRA or to another  403(b)] are
subject to federal income tax withholding at the rate of 10% of the total amount
withdrawn,  unless you elect not to have withholding apply. If you don't want us
to withhold  on this  amount,  you may send us a written  notice not to have the
federal  income tax withheld.  Your written  notice is valid for six months from
the date of  receipt  at  American  Century.  Even if you plan to roll  over the
amount you withdraw to another tax-deferred  account, the withholding rate still
applies to the withdrawn  amount unless we have received a written notice not to
withhold federal income tax within six months prior to the withdrawal.

When  you plan to  withdraw,  you may  make  your  election  by  completing  our
Exchange/  Redemption form or an IRS Form W-4P. Call American Century for either
form.  Your  written  election  is valid  for only six  months  from the date of
receipt at American Century. You may revoke your election at any time by sending
a written notice to us.

Remember,  even if you elect not to have income tax withheld, you are liable for
paying income tax on the taxable portion of your withdrawal. If you elect not to
have income tax withheld or you don't have enough income tax  withheld,  you may
be responsible  for payment of estimated tax. You may incur  penalties under the
estimated  tax rules if your  withholding  and  estimated  tax  payments are not
sufficient.


Semiannual Report          Share Class and Retirement Account Information     21


                                     NOTES


22   Notes                                          American Century Investments


                                     NOTES


Semiannual Report                                                   Notes     23


                             BACKGROUND INFORMATION

INVESTMENT PHILOSOPHY AND POLICIES

The  American  Century  Group  consists of  moderate  risk and  specialty  funds
including  conservative  equity,  balanced,  asset  allocation,   gold,  natural
resources, utilities and real estate funds. In general, aside from the specialty
funds which have unique  risks,  this fund group is for  investors  seeking core
portfolio holdings in the middle ground between aggressive stock funds and money
market and bond funds.

AMERICAN  CENTURY  BALANCED's  investment  philosophy  focuses on four important
principles:

We  attempt  to keep  the  fund  fully  invested  at all  times,  regardless  of
short-term market activity.  Experience has shown that market gains can occur in
unpredictable  spurts  and that  missing  even some of those  opportunities  may
significantly limit the potential for gain.

For the equity  portfolio,  the management  team seeks to own highly  successful
companies,  which we define as those whose  earnings and revenues are growing at
accelerating rates.

For the fixed-income portfolio, "quality first" is the rule. The management team
seeks  only  investment-grade   bonds--those  rated  in  the  top  four  quality
categories by nationally recognized statistical organizations.

Each  portfolio  is managed by a team,  rather  than by one "star"  manager.  We
believe this allows us to make better, more consistent management decisions.

The fund seeks to provide  long-term growth with less volatility than funds that
are 100%  invested in growth  stocks.  The fund keeps about 60% of its assets in
the  stocks  of firms  with  accelerating  growth  rates.  Under  normal  market
conditions, the remaining assets are held in quality intermediate-term bonds.

COMPARATIVE INDICES

The indices listed below are used in the report to serve as a comparison for the
performance  of the  fund.  They  are  not  investment  products  available  for
purchase.

The BLENDED  INDEX is considered  the  benchmark  for Balanced.  It combines two
widely known indices in  proportion  to the asset mix of the fund.  Accordingly,
60% of the index is  represented  by the S&P 500,  which reflects the 60% of the
fund's assets invested in equity  securities.  The remaining 40% of the index is
represented  by  the  Lehman  Intermediate   Government/Corporate  Index,  which
reflects the 40% of the fund's assets  invested in  intermediate-term  bonds and
other fixed-income securities.

The LEHMAN  INTERMEDIATE  GOVERNMENT/CORPORATE  INDEX is considered to represent
the  performance  of  a  portfolio  of  intermediate-term  U.S.  government  and
corporate  bonds.  The index  includes the Lehman  Government and Corporate Bond
Indices,  which are composed of U.S. government,  Treasury and agency securities
with one- to 10-year maturities, as well as corporate and Yankee bonds with one-
to 10-year maturities.

The S&P 500 is a capitalization-weighted  index of the stocks of the 500 largest
publicly traded U.S. companies.  Created by Standard & Poor's Corporation, it is
considered to be a broad measure of U.S. stock market performance.

FUND MANAGEMENT TEAM LEADERS

  EQUITY PORTFOLIO:
  Portfolio Manager        Jim Stowers III
  Portfolio Manager        Bruce Wimberly

  FIXED-INCOME PORTFOLIO:
  Portfolio Manager        Bud Hoops
  Portfolio Manager        Jeff Houston


24   Background Information                         American Century Investments


                                    GLOSSARY

FIXED INCOME TERMS

o CREDIT QUALITY  reflects the financial  strength of a debt security issuer and
the likelihood of timely payment of interest and principal.

o DURATION  is a measure  of the  sensitivity  of a fixed  income  portfolio  to
changes in interest rates. As the duration of a portfolio increases,  the impact
of a change in interest rates on the value of the portfolio also increases.

o STANDARD & POOR'S (S&P) is an independent rating company,  one of the two best
known in the U.S. (the other is Moody's).  The credit  ratings issued by S&P and
Moody's  reflect  the  perceived  financial  strength  (credit  quality) of debt
issuers.  Debt securities rated "investment  grade" (deemed to be of high enough
credit quality to be appropriate  investments for banks and other  institutions)
by S&P are those rated BBB or higher (the highest rating is AAA).

o WEIGHTED AVERAGE MATURITY (WAM),  another  measurement of the sensitivity of a
fixed income  portfolio to interest  rate  changes,  indicates  the average time
until the  principal  in the  portfolio  is expected  to be repaid,  weighted by
dollar amount.  The longer the WAM, the more interest rate exposure and interest
rate sensitivity the portfolio has.

RETURNS

o TOTAL  RETURN  figures  show the overall  percentage  change in the value of a
hypothetical  investment  in  the  fund  and  assume  that  all  of  the  fund's
distributions are reinvested.

o AVERAGE ANNUAL RETURNS  illustrate the annually  compounded returns that would
have produced the fund's cumulative total returns if the fund's  performance had
been  constant  over the  entire  period.  Average  annual  returns  smooth  out
variations in a fund's return;  they are not the same as  year-by-year  results.
For  fiscal   year-by-year  total  returns,   please  refer  to  the  "Financial
Highlights" on page 19.

EQUITY TERMS

o  BLUE-CHIP  STOCKS---generally  considered  to  be  the  stocks  of  the  most
established  companies in American  industry.  They are generally large,  fairly
stable  companies that have  demonstrated  consistent  earnings and usually have
long-term growth potential. Examples include General Electric and Coca-Cola.

o CYCLICAL  STOCKS---generally  considered to be stocks whose price and earnings
fluctuations  tend to follow the ups and downs of the business  cycle.  Examples
include the stocks of  automobile  manufacturers,  steel  producers  and textile
operators.

o GROWTH  STOCKS---generally  considered to be the stocks of companies that have
experienced  above-average  earnings  growth and appear  likely to continue such
growth.  These  stocks  often sell at high P/E ratios.  Examples can include the
stocks of high-tech, healthcare and consumer staple companies.

o  LARGE-CAPITALIZATION  ("LARGE-CAP")  Stocks---generally  considered to be the
stocks of companies with a market capitalization (the total value of a company's
outstanding  stock) of more than $5  billion.  These tend to be the stocks  that
make up the Dow  Jones  Industrial  Average,  the S&P 500 and the  Russell  1000
Index.

o  MEDIUM-CAPITALIZATION  ("MID-CAP")  STOCKS---generally  considered  to be the
stocks of companies with a market capitalization (the total value of a company's
outstanding  stock)  between $1  billion  and $5  billion.  These tend to be the
stocks that make up the S&P MidCap 400.

o PRICE/EARNINGS (P/E) RATIO---a stock value measurement  calculated by dividing
a company's stock price by its earnings per share,  with the result expressed as
a multiple  instead of as a  percentage.  (Earnings  per share is  calculated by
dividing the after-tax earnings of a corporation by its outstanding shares.)

o  SMALL-CAPITALIZATION  ("SMALL-CAP")  STOCKS---generally  considered to be the
stocks of companies with a market capitalization (the total value of a company's
outstanding  stock) of less than $1  billion.  These tend to be the stocks  that
make up the Nasdaq Composite Index and the Russell 2000 Index.

o VALUE  STOCKS---generally  considered to be stocks that are purchased  because
they are relatively inexpensive. These stocks are typically characterized by low
P/E ratios.


Semiannual Report                                                Glossary     25


[american century logo]
American
Century(sm)

P.O. Box 419200
Kansas City, Missouri
64141-6200

INVESTOR SERVICES:
1-800-345-2021 or 816-531-5575

Automated Information Line:
1-800-345-8765

TELECOMMUNICATIONS DEVICE FOR THE DEAF:
1-800-634-4113 or 816-444-3485

FAX: 816-340-7962

INTERNET: www.americancentury.com


AMERICAN CENTURY MUTUAL FUNDS, INC.

Investment Manager
AMERICAN CENTURY INVESTMENT MANAGEMENT, INC.
Kansas City, Missouri

This report and the financial  statements contained herein are submitted for the
general  information  of our  shareholders.  The  report is not  authorized  for
distribution  to  prospective  investors  unless  preceded or  accompanied by an
effective prospectus.

American Century Investment Services, Inc.


9706           [recycled logo]
SH-BKT-8636       Recycled
<PAGE>
                               SEMIANNUAL REPORT

                            [american century logo]
                                    American
                                  Century(sm)

                                 April 30, 1997

                                     BENHAM
                                     GROUP

                            Limited-Term Tax-Exempt
                          Intermediate-Term Tax-Exempt
                              Long-Term Tax-Exempt

[front cover]

                               TABLE OF CONTENTS

Report Highlights........................................... 1
Our Message to You.......................................... 2
Period Overview............................................. 3
Municipal Credit Review..................................... 4
Limited-Term Tax-Exempt
     Performance & Portfolio Information.................... 5
     Management Q & A....................................... 6
     Schedule of Investments................................ 9
     Financial Highlights...................................30
Intermediate-Term Tax-Exempt
     Performance & Portfolio Information....................11
     Management Q & A.......................................12
     Schedule of Investments................................15
     Financial Highlights...................................31
Long-Term Tax-Exempt
     Performance & Portfolio Information....................18
     Management Q & A.......................................19
     Schedule of Investments................................22
     Financial Highlights...................................32
Statements of Assets and Liabilities........................25
Statements of Operations....................................26
Statements of Changes in Net Assets.........................27
Notes to Financial Statements...............................28
Background Information
     Investment Philosophy & Policies.......................36
     Comparative Indices....................................36
     Lipper Rankings........................................36
     Portfolio Management Team..............................36
Glossary....................................................37

American Century  Investments offers you nearly 70 fund choices covering stocks,
bonds, money markets,  specialty investments and blended portfolios. To help you
find the funds that may meet your needs, we have divided  American Century funds
into three groups based on investment style and objectives.  These groups, which
appear below, are designed to help simplify your fund decisions.

                  merican Century Investments--Family of Funds

     BENHAM GROUP           AMERICAN CENTURY GROUP       TWENTIETH CENTURY GROUP

  MONEY MARKET FUNDS          ASSET ALLOCATION &
 GOVERNMENT BOND FUNDS          BALANCED FUNDS               U.S. GROWTH FUNDS
DIVERSIFIED BOND FUNDS     CONSERVATIVE EQUITY FUNDS        INTERNATIONAL FUNDS
 MUNICIPAL BOND FUNDS          SPECIALTY FUNDS

Limited-TermTax-Exempt
   Intermediate-Term
      Tax-Exempt
 Long-Term Tax-Exempt


We welcome your comments or questions about this report.  
See the back cover for ways to contact us by mail, phone or e-mail.

Twentieth  Century and the Benham Group are registered marks of American Century
Services Corporation and Benham Management Corporation,  respectively.  American
Century is a service mark of American Century Services Corporation.


                                                    American Century Investments


                               REPORT HIGHLIGHTS

Period Overview

o    The U.S.  economy  grew  vigorously  during the six months  ended April 30,
     1997, while inflation remained relatively subdued.

o    Uncertainty  about  the  strength  of  the  U.S.  economy  caused  shifting
     expectations  for the  direction  of  interest  rates,  limiting  gains for
     municipal bonds.

o    Concerned  that  robust  economic  growth  would  foster a  faster  rate of
     inflation, the Federal Reserve raised short-term interest rates in March.

o    With the  possibility of higher  interest  rates on the horizon,  municipal
     bond yields ended the six months at their highest levels for the period.

Municipal Credit Review

o    Municipal  credit  quality  continued  to  improve,  partially  because  of
     favorable U.S. economic conditions.

o    The number of credit  upgrades  has  continued to improve over the last few
     years; however, that trend has been slowing in recent months.

Limited-Term Tax-Exempt

o    The fund's return  reflected the bearish  environment that prevailed during
     the first four months of 1997.

o    In  mid-March  we began  adjusting  the fund's  average  maturity to better
     reflect the change in the fund's  name and  investment  policies  that took
     place on March 1.

o    Looking forward,  we will likely maintain the fund's bullet structure as an
     added precaution in case rates move sharply higher.

Intermediate-Term Tax-Exempt

o    Reflecting the bearish  environment  that  prevailed  during the first four
     months of 1997, the fund posted modest returns.

o    Though we made only slight  adjustments to the fund's average maturity,  we
     shifted the fund toward more of a bullet structure.

o    Going forward,  we will continue to utilize our strong credit research team
     to add securities that we believe will appreciate in value.

Long-Term Tax-Exempt

o    For the six-month period,  the fund essentially  matched the average return
     of its peers and slightly trailed the return of its benchmark.

o    Choosing a more conservative approach, we maintained the fund's duration (a
     measure of interest rate  sensitivity) in a relatively  narrow range around
     our benchmark.

o    Going forward,  we will likely keep the fund  conservatively  positioned in
     case rates continue to rise.

                                  Limited-Term
                           Total Returns:AS OF 4/30/97
                             6 Months         1.45%*
                             1 Year           3.87%
                            Net Assets:$45.6 million
                            (AS of 4/30/97)
                           Inception Date:      3/1/93
                           Ticker Symbol:   TWTSX

                                Intermediate-Term
                           Total Returns:AS OF 4/30/97
                             6 Months         1.50%*
                             1 Year           4.85%
                            Net Assets:$72.2 million
                            (AS of 4/30/97)
                           Inception Date:      3/2/87
                           Ticker Symbol:   TWTIX

                                   Long-Term
                           Total Returns:AS OF 4/30/97
                             6 Months         1.63%*
                             1 Year           7.10%
                            Net Assets:$56.3 million
                            (AS of 4/30/97)
                           Inception Date:      3/2/87
                           Ticker Symbol:   TWTLX

                           * Not annualized.

                 Many of the investment terms in this report are
                       defined in the Glossary on page 37.


Semiannual Report                                         Report Highlights    1

                               OUR MESSAGE TO YOU

              [photo of James E. Stowers III and James M. Benham]

April 30,  1997,  marked the end of an eventful  period for our company and U.S.
municipal  bond  markets.  Though  municipal  bond  returns  were modest for the
six-month  period,  they exceeded those of Treasury  securities as  accelerating
first-quarter  economic growth sent bond yields higher.  In the following pages,
our investment management team provides further details about the market and how
your fund was managed during the period.

In January,  nearly two years of integration  between  Twentieth Century and The
Benham  Group   culminated  when  we  began  serving  you  as  American  Century
Investments.  Under this new name we have  combined  our  offerings of nearly 70
funds.

The new name also introduces three new groupings for the funds--the Benham Group
(money market and bond funds),  the American  Century  Group (asset  allocation,
balanced,  conservative  equity and specialty  funds) and the Twentieth  Century
Group (aggressive  growth and international  equity funds).  The Tax-Exempt Bond
funds have joined the Benham  Group  because  their  investment  goals match key
attributes of that group.

By now,  you should have  received a proxy  statement  and ballot that  proposes
several  changes to your fund. In order to  streamline  and simplify our list of
fund  offerings,  we are proposing to merge several funds whose  characteristics
and  investment  objectives are very similar or identical.  The proxy  statement
includes  proposals  to merge  the  Intermediate-Term  Tax-Exempt  fund into the
existing  Intermediate-Term Tax-Free fund and the Long-Term Tax-Exempt fund into
the existing  Long-Term  Tax-Free  fund.  It also  proposes that the name of the
Limited-Term  Tax-Exempt fund be changed to the Limited-Term  Tax-Free fund. The
proxy statement  contains more details about the proposed  changes;  we strongly
encourage  you to read it carefully  and take part in the proxy vote if you have
not already done so.

In  reviewing  this report,  you may notice some  changes.  Based on  investors'
feedback,  our  shareholder  reports have been  redesigned  with added features,
including a report  summary,  a glossary,  more charts and graphs,  and expanded
management Q & A and background information sections.

These are  examples  of how we  continue  working  to  provide  information  and
services  that are useful and  convenient  to  investors  in our funds.  We look
forward to sharing other helpful changes with you.

Sincerely,

/s/James E. Stowers III                     /s/James M. Benham
James E. Stowers III                        James M. Benham
President and Chief Executive Officer       Vice Chairman
American Century Companies                  American Century Companies


2    Our Message to You                             American Century Investments


                                PERIOD OVERVIEW

U.S. Economy

The U.S.  economy  grew  vigorously  during the six months ended April 30, 1997.
Fueling  surprisingly  strong growth were low  unemployment,  strong job growth,
consumer  spending and a robust  housing market that hovered near record levels.
This  combination  of  factors  caused the  economy to expand at a healthy  3.8%
annual rate during the fourth quarter of 1996. During the first quarter of 1997,
economic growth continued to pick up steam, reaching a 10-year high of 5.8%.

Concerned that vigorous economic growth would foster a faster rate of inflation,
the Federal Reserve (the Fed) raised short-term interest rates in March, marking
the first increase since February 1995.

While the economy continued its impressive growth, inflation remained relatively
subdued. Overall consumer prices--as measured by the government's consumer price
index--  rose at a 3.2% annual rate during the  six-month  period.  This unusual
combination of strong growth and relatively  subdued inflation sent a barrage of
mixed signals to bond investors.

Municipal Bond Market

Municipal  bonds produced modest returns for the six-month  period.  Uncertainty
concerning the strength of the U.S. economy caused shifting expectations for the
direction of interest rates, limiting bond market gains.

The effects of these shifts are demonstrated by the  accompanying  graph. As the
six-month period began,  evidence of a moderating economy finally convinced many
municipal bond investors that inflation would remain under control. By December,
municipal  yields  had  fallen 15 to 18 basis  points  from where they began the
period,  reflecting investor optimism that well-contained  inflation would allow
the Fed to hold short-term interest rates steady.

Helping the  late-1996  rally was strong  demand from  insurance  companies  for
longer-maturity  municipal securities.  Many of these companies made "crossover"
buys--that is, they  purchased  municipal  bonds instead of  comparable-maturity
Treasury  bonds  because  of  the  relatively   attractive   yields  offered  by
municipals.

However, bond yields headed higher at the end of the first quarter of 1997, as a
March tightening move by the Fed sparked concern that interest rates were upward
bound.  As a result,  municipal  bond  yields at the end of April  were at their
highest levels for the period.

Although  municipal  yields  rose  overall  during  the six  months,  municipals
weathered  the  market's   gyrations   much  better  than  did  their   Treasury
counterparts  as bond prices fell.  The change in bond yields  illustrates  this
divergence--yields  on  short-term  municipal  bonds ended the period  around 25
basis points higher than where they began,  while yields on short-term  Treasury
bonds ended nearly 50 basis points higher. Among longer-term securities, 30-year
municipal  yields ended  virtually  unchanged,  while  30-year  Treasury  yields
finished the period nearly 25 basis points higher.

Robust demand from retail investors helped fuel the  outperformance of municipal
securities,  particularly as interest rates rose during the first four months of
1997. At the same time, new municipal  issuance  remained fairly low compared to
the early  1990s.  This  favorable  supply and demand  relationship  also helped
dampen market volatility.

[line graph - data below]

Shifting Municipal Yield Curve

Years to Maturity      10/31/96          12/5/96           4/30/97

0.25                     3.25             3.10              3.48
0.50                     3.45             3.30              3.66
1.00                     3.65             3.50              3.92
2.00                     3.95             3.80              4.22
3.00                     4.15             4.00              4.42
4.00                     4.30             4.12              4.57
5.00                     4.40             4.22              4.67
6.00                     4.50             4.32              4.76
7.00                     4.60             4.42              4.84
8.00                     4.70             4.52              4.91
9.00                     4.80             4.62              4.98
10.00                    4.90             4.72              5.05
11.00                    4.98             4.81              5.12
12.00                    5.07             4.90              5.18
13.00                    5.15             4.98              5.25
14.00                    5.24             5.07              5.31
15.00                    5.32             5.16              5.38
16.00                    5.35             5.19              5.41
17.00                    5.38             5.22              5.44
18.00                    5.42             5.24              5.47
19.00                    5.45             5.27              5.50
20.00                    5.48             5.30              5.53
21.00                    5.49             5.31              5.54
22.00                    5.50             5.32              5.55
23.00                    5.50             5.32              5.55
24.00                    5.51             5.33              5.56
25.00                    5.52             5.34              5.57
26.00                    5.52             5.34              5.57
27.00                    5.53             5.35              5.58
28.00                    5.53             5.35              5.58
29.00                    5.54             5.36              5.59
30.00                    5.54             5.36              5.59
Source: Bloomberg Financial Markets


Semiannual Report                                           Period Overview    3


                            MUNICIPAL CREDIT REVIEW

Municipal credit quality  continued to improve during the six months ended April
30, 1997, in part because of the favorable economic conditions discussed on page
3. Credit upgrades  outpaced credit  downgrades by more than 3 to 1 during 1996.
The  number of credit  upgrades  has  continued  to  improve  since  1995,  when
downgrades  outnumbered upgrades;  however, in recent months that trend has been
slowing.

Regionally, the Rocky Mountain states and the Southwest continued to display the
strongest  economic growth in the nation,  and this strength has expanded to the
West Coast (see the accompanying graph). California's economic turnaround is the
result  of strong  growth in the  high-technology  industries  and  California's
position as the nation's leading  exporter.  The Midwest  continued to grow at a
relatively  steady  pace,  while the  southeastern  portion of the country  also
remained  healthy.  The Great Lakes areas,  Louisiana,  the Mid-Atlantic and the
Northeast  still lag the rest of the nation,  but even these  regions  have seen
improved economic conditions in 1996 and 1997.

General  obligation (GO) bonds and other forms of  tax-supported  municipal debt
have benefited from the increased tax revenues that healthy  economic  growth is
providing.  However,  federal  policy  decisions  related to health and  welfare
reform  may pose  longer-term  concerns  for  state  and  local  governments.  A
widespread  trend toward  managed care  continues to cause credit  pressures for
health care. In addition,  many bonds issued by public power companies are being
adversely affected by the deregulation of the electric utilities industry.

Please keep in mind that this analysis  provides only a broad glimpse of general
municipal market trends.  Growing market  complexity and issue disparities point
to a continuing need for thorough  case-by-case credit analysis that encompasses
more than sector analysis alone can provide--although sector analysis remains an
integral element in municipal research.

CREDIT QUALITY TRENDS
(graphic of U.S. map)

Improving:
Arizona
California
Colorado
Georgia
Idaho
Massachussetts
Minnesota
Mississippi
Nevada
New Hampshire
New Mexico
North Carolina
Oregon
South Dakota
South Carolina
Tennessee
Texas
Utah
Virginia
Washington
Wisconsin

Stable:
(all other states)


4    Municipal Credit Review                        American Century Investments

<TABLE>
<CAPTION>
                            LIMITED-TERM TAX-EXEMPT


                                             30-Day                  30-Day Tax-Equivalent Yields
                                               SEC           28%           31%           36%           39.6%
                                              Yield      Tax Bracket   Tax Bracket   Tax Bracket    Tax Bracket

CURRENT YIELDS AS OF APRIL 30, 1997
<S>                                           <C>           <C>           <C>           <C>            <C>  
Limited-Term Tax-Exempt                       4.05%         5.63%         5.87%         6.33%          6.71%


                                                                               AVERAGE ANNUAL RETURNS
                                                          6 MONTHS       1 YEAR        3 YEARS     LIFE OF FUND
TOTAL RETURNS AS OF APRIL 30, 1997
Limited-Term Tax-Exempt ..................................  1.45%         3.87%         4.45%          4.07%
Merrill Lynch 0- to 3-Year Muni Index ....................  1.47%         3.74%         4.25%          3.97%
Average Short Municipal
Debt Fund(1) .............................................  1.65%         4.01%         4.31%         3.83%(2)
Fund's Ranking Among Short
Municipal Debt Funds(1) ..................................   --       13 out of 30   6 out of 18    2 out of 11
</TABLE>

(1) According to Lipper Analytical Services.
(2) Return since 3/31/93, the date nearest the fund's inception for which return
    data are available. Inception date was March 1, 1993.

See pages 36-37 for more information  about returns,  the comparative  index and
Lipper fund rankings.

[mountain graph - data below]

GROWTH OF $10,000 OVER THE LIFE OF THE FUND

Limited-Term Tax-Exempt                 $11,809
Merrill Lynch 0- to 3-Year Muni Index   $11,762

           Limited-Term Tax-Exempt      Merrill Lynch 0- to 3-Year Muni Index
03/01/93          $10,000                             $10,000
Mar-93            $10,014                              $9,992
Jun-93            $10,132                             $10,110
Sep-93            $10,227                             $10,149
Dec-93            $10,336                             $10,322
Mar-94            $10,322                             $10,318
Jun-94            $10,426                             $10,395
Sep-94            $10,524                             $10,498
Dec-94            $10,592                             $10,457
Mar-95            $10,791                             $10,693
Jun-95            $10,965                             $10,903
Sep-95            $11,111                             $11,063
Dec-95            $11,307                             $11,212
Mar-96            $11,365                             $11,324
Jun-96            $11,436                             $11,402
Sep-96            $11,565                             $11,535
Dec-96            $11,723                             $11,673
Mar-97            $11,769                             $11,728
Apr-97            $11,809                             $11,762

Past  performance  does not  guarantee  future  results.  Investment  return and
principal  value will fluctuate,  and redemption  value may be more or less than
original cost. The line representing the fund's total return includes  operating
expenses (such as transaction  costs and management  fees) that reduce  returns,
while the total return line of the index does not.

PORTFOLIO AT A GLANCE
                                 4/30/97         10/31/96
Number of Securities               40               44
Weighted Average Maturity       3.6 years        2.3 years
Average Duration                3.0 years        2.1 years
Expense Ratio                    0.60%*            0.60%

* Annualized.


Semiannual Report                                   Limited-Term Tax-Exempt    5

                            LIMITED-TERM TAX-EXEMPT

Management Q & A

An inverview  with Joel Silva, a municipal  portfolio  manager on the Tax-Exempt
funds management team.

How did the fund perform?

The fund's return reflects the bearish bond  environment  that prevailed  during
the first four months of 1997.  For the  six-month  period ended April 30, 1997,
the fund's total return was 1.45%, compared with the 1.65% average return of the
30 funds in Lipper's "Short  Municipal Debt Funds" category and the 1.47% return
of the fund's  benchmark,  the Merrill Lynch 0- to 3-Year  Municipal Bond Index.
(See the Total  Returns  table on the previous  page for other fund  performance
comparisons.)

The fund's average maturity lengthened from 2.3 years to 3.6 years by the end of
the  period.  Was the change  made to reflect  the  fund's  recent  shift from a
"short-term" fund to a "limited-term" fund?

That's correct.  Until mid-March,  we made only slight adjustments to the fund's
average  maturity,  within a narrow  range  around  2.5  years.  At that time we
decided to take  advantage of rising  interest rates and began  lengthening  the
fund's  average  maturity to better  reflect the fund's new name and  investment
policies.

We are in the process of changing the fund's  Lipper  category  from its current
designation to Lipper's "Other State's Short-Intermediate  Municipal Debt Funds"
category,  which contains  municipal funds that maintain  average  maturities of
three to five years.

[bar graph - data below]

LIMITED-TERM TAX-EXEMPT'S ONE-YEAR RETURNS SINCE INCEPTION
(Periods ended April 30)

            Limited-Term Tax-Exempt      Merrill Lynch Muni (O- to 3-Year) Index

4/30/93                0.50%                                0.36%
4/30/94                3.12%                                3.43%
4/30/95                4.41%                                3.56%
4/30/96                5.08%                                5.47%
4/30/97                3.87%                                3.74%

This graph  illustrates the fund's returns since its inception and compares them
with the index's returns.  The fund's total returns include operating  expenses,
while the index's do not. See page 36 for a definition of the index.

* Return from the fund's 3/1/93 inception date to 4/30/93.


6    Limited-Term Tax-Exempt                        American Century Investments


                            LIMITED-TERM TAX-EXEMPT

We think it important to note that although the fund underperformed its old peer
group for the six-month period,  the fund's  year-to-date  returns through April
placed it among the old peer group's higher performers, and allowed it to finish
even better among its new peer group.

You increased the fund's holdings of municipals  rated BBB from 16% to 26%. What
was your strategy?

The main  vehicle we used to enhance  the fund's  returns  during the period was
careful selection of lower-rated municipal bonds. With that in mind, we expanded
the amount of securities  rated BBB in the fund to provide  higher yields and in
anticipation of continued credit strength across the nation.

Nationally improving credit conditions also caused the yield spread--or interest
rate difference--between comparable-maturity municipal securities with different
credit ratings to decrease as investors  reached for higher yields. We were able
to overcome  this  obstacle and locate  attractively  valued  securities  thanks
largely to our strong credit research team.

The percentage of GOs in the fund's portfolio  dropped by almost a third,  while
the percentage of COPs and lease agreements tripled. Why the change?

In a market where  interest  rates tend to stay within a given  range,  interest
payments  generally  contribute  more to a fund's  returns.  Because GOs tend to
offer lower yields than COPs and lease  agreements,  we chose to replace some of
our maturing GOs with New York-issued COPs and leases.

We purchased  New York COPs and leases for the fund's  portfolio  because of the
state's generally  improving economic  conditions.  As other market participants
began to realize the potential value of these  securities,  rising demand caused
these COPs and leases to appreciate.

What is your outlook for the municipal market over the next six months?

Bond yields rose during the first four months of 1997,  largely because the U.S.
economy  showed  faster-than-normal  growth as wages edged  higher.  While these
factors led the Federal Reserve (the Fed) to raise short-term  interest rates in
March,  the recent


TOP FIVE STATES (% of fund investments)
                 As of                      As of
                 4/30/97                   10/31/9
New York           15%      Texas            10%
Missouri           10%      California        9%
Texas               8%      Pennsylvania      7%
Colorado            7%      Arizona           7%
Florida             6%      Colorado          6%

[pie charts]
PORTFOLIO  COMPOSITION BY SECURITY TYPE (as of 4/30/97) 
Revenue Bonds 46% 
GO 26%
COPs/Leases 22% 
Prerefunded/ETM 6%

PORTFOLIO COMPOSITION BY SECURITY TYPE (as of 10/31/96) 
Revenue Bonds 48% 
GO 36%
Prerefunded/ETM 9% 
COPs/Leases 7%


Semiannual Report                                   Limited-Term Tax-Exempt    7


                            LIMITED-TERM TAX-EXEMPT

moderating  trend of  economic  growth  allowed the Fed to hold  interest  rates
steady  after its May  meeting.  Whether  the Fed will  continue to stand pat or
decide to raise  rates  again soon is  uncertain.  Current  economic  conditions
suggest that inflation can remain tame even as the economy flourishes.

As such, we believe that the Fed should not need to raise rates  dramatically to
keep inflation within  reasonable  levels.  If U.S. economic growth slows of its
own accord, municipal securities could rally; but with wage pressures increasing
the threat of a Fed rate hike, any signs of an  overheating  economy will likely
push municipal bond prices lower.

Another development we will monitor closely is the relative  performance between
municipal  and  Treasury  securities  (see  page  3).  Lately,  municipals  have
significantly  outperformed  Treasurys, a situation caused in part by relatively
low municipal  issuance.  Although municipal issuance should remain fairly light
in the near future,  the  likelihood  that  municipal  bonds will  continue this
outperformance is  diminishing--their  prices have reached levels where they are
considered  historically  expensive  compared with like-maturity  Treasurys.  If
municipals  continue this trend,  investor demand could eventually shift back to
Treasurys, removing a key supporting factor for municipal bond prices.

With this outlook in mind, what are your plans for the fund going forward?

Currently,  the market  seems to expect that  economic  growth will  continue to
slow, allowing the Fed to hold short-term rates steady; however, we are inclined
to somewhat  disagree  with that notion.  As such,  we will likely  maintain the
fund's  bullet  structure  for now as an added  precaution  in case  rates  move
sharply  higher or lower.  If the  economic  outlook  changes  dramatically,  we
believe that this position will allow us to respond appropriately.  We will also
continue  to utilize our credit  research  team to look for  securities  that we
believe will add value to the fund's returns.

[pie charts]

PORTFOLIO COMPOSITION BY CREDIT RATING (as of 4/30/97)
AAA 51%
AA 17%
A 6%
BBB 26%

PORTFOLIO COMPOSITION BY CREDIT RATING (as of 10/31/96)
AAA 45%
AA 20%
A 19%
BBB 16%


8    Limited-Term Tax-Exempt                        American Century Investments


                            SCHEDULE OF INVESTMENTS
                            LIMITED-TERM TAX-EXEMPT

APRIL 30, 1997 (UNAUDITED)

Principal Amount                ($ in Thousands)                        Value
- --------------------------------------------------------------------------------

MUNICIPAL SECURITIES
Alaska--1.6%
$       735   Anchorage Alaska GO, Series A,
                5.50%, 8/1/99 (AMBAC)                                $  750
                                                                     ------
Arizona--3.9%
      1,000   Arizona State Transportation Board
                Excise Tax Rev., (Maricopa County),
                5.60%, 7/1/02 (AMBAC)                                 1,034
        750   Maricopa County Certificates of
                Participation, 5.625%, 6/1/00                           762
                                                                     ------
                                                                      1,796
                                                                     ------
California--2.2%
      1,000   Central Valley Financing Auth. Rev.,
                (Cogeneration Project), 5.00%,
                7/1/98                                                1,005
                                                                     ------
Colorado--6.9%
      1,140   Denver Colorado City & County
                Airport Rev., Series D, 6.80%,
                11/15/97                                              1,155
      1,000   Denver Colorado City & County
                Airport Rev., Series B, 5.25%,
                11/15/02 (MBIA)                                       1,011
      1,000   Highlands Ranch Metropolitan
                District #2, 6.00%, 6/15/02 (FSA)                     1,053
                                                                     ------
                                                                      3,219
                                                                     ------
Connecticut--4.4%
      2,000   Connecticut State Special Tax
                Obligation Rev., (Transportation
                Infrastructure), 5.50%, 10/1/00
                (FGIC)                                                2,057
                                                                     ------
Florida--5.6%
      1,500   Hillsborough County School Board
                Sales Tax Rev., 5.00%, 10/1/02
                (AMBAC)                                               1,512
      1,000   Jacksonville Electric Auth. Rev., (St.
                John's River), 6.00%, 10/1/04                         1,062
                                                                     ------
                                                                      2,574
                                                                     ------

Principal Amount                ($ in Thousands)                        Value
- --------------------------------------------------------------------------------

Guam--3.2%
$     1,000   Government of Guam GO, Series A,
                5.50%, 8/15/97                                       $1,003
        500   Guam Power Auth. Rev., Series A,
                5.20%, 10/1/97                                          502
                                                                     ------
                                                                      1,505
                                                                     ------
Idaho--2.1%
      1,000   ADA & Canyon Counties Joint
                School District No. 2 GO, 4.25%,
                7/30/99                                                 997
                                                                     ------
Illinois--4.4%
      1,015   Cook County GO, Series A, 5.75%,
                11/15/99 (MBIA)                                       1,046
      1,000   Southern Illinois University Rev.,
                (Housing and Auxiliary Facilities),
                5.00%, 4/1/00 (MBIA)                                  1,009
                                                                     ------
                                                                      2,055
                                                                     ------
Maryland--2.2%
      1,000   Baltimore County GO, 5.00%,
                8/1/01                                                1,014
                                                                     ------
Michigan--4.1%
        385   Detroit Michigan GO, Series B,
                5.10%, 4/1/99                                           387
        500   Michigan Hospital Finance Auth.
                Rev., (Genesys Health Systems),
                6.40%, 10/1/97                                          504
      1,000   Michigan State Building Auth. Rev.,
                Series I, 5.00%, 10/1/00                              1,012
                                                                     ------
                                                                      1,903
                                                                     ------
Minnesota--2.8%
      1,200   Minneapolis Hospital Rev.,
                (Lifespan Inc.- Abbott
                Northwestern), 7.00%, 12/1/01,
                Prerefunded 12/1/99 at 102%
                of Par(1)                                             1,295
                                                                     ------
Mississippi--2.1%
      1,000   Mississippi State Lease Rev.
                Certificates of Participation,
                Series A, 4.60%, 4/15/99
                (AMBAC)                                               1,000
                                                                     ------

See Notes to Financial Statements


Semiannual Report                                   Limited-Term Tax-Exempt    9


                            SCHEDULE OF INVESTMENTS
                            LIMITED-TERM TAX-EXEMPT

APRIL 30, 1997 (UNAUDITED)

Principal Amount                ($ in Thousands)                        Value
- --------------------------------------------------------------------------------

Missouri--10.2%
$     1,000   Kansas City Port Auth. Facilities
                Rev., Series A, (Riverfront Park
                Project), 5.75%, 10/1/98                             $1,015
      1,675   North Kansas City Missouri School
                District GO, 5.00%, 3/1/00                            1,693
      2,000   Springfield Missouri State Highway
                Improvement Corp. Rev., 5.05%,
                8/1/03 (AMBAC)                                        2,007
                                                                     ------
                                                                      4,715
                                                                     ------
New Jersey--3.9%
      1,750   West Windsor Plainsboro GO,
                5.25%, 12/1/02 (FGIC)                                 1,789
                                                                     ------
New York--14.5%
      2,145   Municipal Assistance Corp. for City
                of New York, Series I, 5.25%,
                7/1/02                                                2,179
      1,000   New York City GO, Series A,
                6.25%, 8/1/03                                         1,045
      2,000   New York State Certificates of
                Participation, 4.40%, 8/1/98                          2,001
      1,000   New York State Serial Bonds GO,
                6.70%, 11/15/99                                       1,052
        445   Port Auth. of New York and New
                Jersey Rev., Consolidated Notes,
                Series SS, 4.90%, 9/1/97                                445
                                                                     ------
                                                                      6,722
                                                                     ------
Ohio--4.5
      2,070   Ohio State Building Auth. Rev.,
                Series A, (Highway Safety
                Building), 5.00%, 10/1/03
                (AMBAC)                                               2,075
                                                                     ------
Pennsylvania--4.4%
      2,000   Philadelphia Gas Works Rev., 14th
                Series, 5.40%, 7/1/98                                 2,024
                                                                     ------
South Carolina--2.3%
        145   Piedmont Municipal Power Agency
                Rev., Series A, 6.00%,
                1/1/02 (FGIC)(1)                                        152
        855   Piedmont Municipal Power Agency
                Rev., Series A, 6.00%, 1/1/02
                (FGIC)                                                  893
                                                                     ------
                                                                      1,045
                                                                     ------

Principal Amount                ($ in Thousands)                        Value
- --------------------------------------------------------------------------------

Texas--7.8%
$     1,780   Brownsville Utility System Rev.,
                5.00%, 9/1/00 (AMBAC)                              $  1,798
      1,000   Colorado River Municipal Water
                District Rev., Series A, 8.50%,
                1/1/01, Prerefunded 1/1/01 at
                100% of Par (AMBAC)(1)                                1,126
        685   Denison Hospital Auth. Rev.,
                (Texoma Medical Center), 5.00%,
                8/15/00                                                 684
                                                                     ------
                                                                      3,608
                                                                     ------
Virginia--2.2%
      1,000   Virginia State Public Building Auth.
                Rev., Series A, 5.70%, 8/1/00                         1,033
                                                                     ------
Washington--4.7%
      1,680   Snohomish County Public Utility
                District #1 Electric Rev., Series B,
                4.75%, 1/1/00                                         1,674
        515   Washington Public Power Supply
                System Rev., Series C, (Nuclear
                Project #1), 4.50%, 7/1/98                              517
                                                                     ------
                                                                      2,191
                                                                     ------

TOTAL INVESTMENT SECURITIES--100.0%                                 $46,372
   (Cost $46,419)                                                   =======

Notes to Schedule of Investments 
AMBAC = AMBAC Indemnity Corp.
FGIC = Financial Guaranty Insurance Company
FSA = Financial Security Association
GO = General Obligation
MBIA = Municipal Bond Insurance Association
(1)  Escrowed in U.S. Government Securities.

See Notes to Financial Statements


10   Limited-Term Tax-Exempt                        American Century Investments


<TABLE>
<CAPTION>
                          INTERMEDIATE-TERM TAX-EXEMPT

                                             30-Day                  30-Day Tax-Equivalent Yields
                                               SEC           28%           31%           36%           39.6%
                                              Yield      Tax Bracket   Tax Bracket   Tax Bracket    Tax Bracket

CURRENT YIELDS AS OF APRIL 30, 1997
<S>                                           <C>           <C>           <C>           <C>            <C>  
Intermediate-Term Tax-Exempt                  4.57%         6.35%         6.62%         7.14%          7.57%

                                                                        AVERAGE ANNUAL RETURNS
                                            6 MONTHS       1 YEAR        3 YEARS      5 YEARS        10 YEARS
TOTAL RETURNS AS OF APRIL 30, 1997
Intermediate-Term Tax-Exempt ...............  1.50%         4.85%         5.60%         5.71%          6.28%
Lehman 5-Year General Obligation Index .....  1.58%         4.81%         5.71%         5.98%          6.61%
Average Intermediate Municipal
Debt Fund(1) ...............................  1.55%         4.97%         5.63%         6.00%          6.87%
Fund's Ranking Among Intermediate
Municipal Debt Funds(1) ....................   --       0 out of 136  51 out of 98  24 out of 34   15 out of 18

(1)  According to Lipper Analytical Services.
</TABLE>

See pages 36-37 for more information  about returns,  the comparative  index and
Lipper fund rankings.

[mountain grpah - data below]

GROWTH OF $10,000 OVER TEN YEARS

Value on 04/30/97

Intermediate-Term Tax-Exempt   $18,381
Lehman 5-Year GO Index         $18,972

            Intermediate-Term Tax-Exempt    Lehman 5-Year GO Index

Apr-87                $10,000                      $10,000
Jun-87                $10,219                      $10,211
Sep-87                $10,078                      $10,001
Dec-87                $10,406                      $10,383
Mar-88                $10,612                      $10,705
Jun-88                $10,785                      $10,750
Sep-88                $10,909                      $10,872
Dec-88                $11,032                      $10,939
Mar-89                $11,021                      $10,908
Jun-89                $11,367                      $11,421
Sep-89                $11,477                      $11,548
Dec-89                $11,766                      $11,800
Mar-90                $11,813                      $11,857
Jun-90                $12,001                      $12,123
Sep-90                $12,131                      $12,250
Dec-90                $12,506                      $12,657
Mar-91                $12,770                      $12,929
Jun-91                $12,965                      $13,156
Sep-91                $13,359                      $13,624
Dec-91                $13,764                      $14,080
Mar-92                $13,840                      $14,069
Jun-92                $14,224                      $14,527
Sep-92                $14,490                      $14,888
Dec-92                $14,751                      $15,124
Mar-93                $15,117                      $15,508
Jun-93                $15,474                      $15,875
Sep-93                $15,868                      $16,218
Dec-93                $16,089                      $16,417
Mar-94                $15,519                      $15,899
Jun-94                $15,699                      $16,112
Sep-94                $15,823                      $16,243
Dec-94                $15,757                      $16,190
Mar-95                $16,414                      $16,846
Jun-95                $16,790                      $17,275
Sep-95                $17,184                      $17,747
Dec-95                $17,636                      $18,072
Mar-96                $17,550                      $18,128
Jun-96                $17,601                      $18,208
Sep-96                $17,916                      $18,504
Dec-96                $18,331                      $18,907
Mar-97                $18,293                      $18,877
Apr-97                $18,381                      $18,972

Past  performance  does not  guarantee  future  results.  Investment  return and
principal  value will fluctuate,  and redemption  value may be more or less than
original cost. The line representing the fund's total return includes  operating
expenses (such as transaction  costs and management  fees) that reduce  returns,
while the total return line of the index does not.

PORTFOLIO AT A GLANCE
                                 4/30/97         10/31/96
Number of Securities               50               57
Weighted Average Maturity       7.2 years        7.1 years
Average Duration                5.4 years        5.3 years
Expense Ratio                    0.60%*            0.60%

* Annualized.


Semiannual Report                              Intermediate-Term Tax-Exempt   11


                          INTERMEDIATE-TERM TAX-EXEMPT

Management Q & A

An inverview  with Joel Silva, a municipal  portfolio  manager on the Tax-Exempt
funds management team.

How did the fund perform?

Reflecting the bearish bond  environment  that  prevailed  during the first four
months of 1997, the fund posted modest returns.  For the six-month  period ended
April 30,  1997,  the fund's total  return was 1.50%,  essentially  matching the
1.55% average return of the 136 funds in Lipper's  "Intermediate  Municipal Debt
Funds"  category  and the 1.58% return of the fund's  benchmark.  (See the Total
Returns table on the previous page for other fund performance comparisons.)

Did you change the fund's positioning during the period?

We made only slight adjustments to the fund's average maturity,  but we did make
some  structural  changes  during  the  period.  Choosing  a  more  conservative
approach,  we kept the fund's  average  maturity in a  relatively  narrow  range
around 7 years, lengthening or shortening slightly as conditions warranted.

The fund's barbell  structure  buoyed its returns in early 1997 as concerns that
the  Federal  Reserve  would  raise  rates  caused the yield  curve to  flatten.
However, we have recently been shifting the fund's structure to more of a bullet
position--which  tends to perform  best when the yield curve is moving from flat
to steep--because economic fundamentals seem to be changing.

[bar graph - data below]

INTERMEDIATE-TERM  TAX-EXEMPT'S ONE-YEAR RETURNS FOR THE PAST TEN YEARS (Periods
ended April 30)

           Intermediate-Term Tax-Exempt   Lehman 5-Year GO Index

4/30/88                6.72%                       8.03%
4/30/89                4.26%                       2.71%
4/30/90                5.46%                       6.52%
4/30/91                9.89%                      10.77%
4/30/92                7.99%                       8.41%
4/30/93                9.32%                       9.97%
4/30/94                2.53%                       2.89%
4/30/95                5.38%                       5.18%
4/30/96                6.59%                       7.16%
4/30/97                4.85%                       4.81%

This graph  illustrates  the fund's  returns over the past 10 years and compares
them with the  index's  returns.  The fund's  total  returns  include  operating
expenses, while the index's do not. See page 36 for a definition of the index.


12   Intermediate-Term Tax-Exempt                   American Century Investments


                          INTERMEDIATE-TERM TAX-EXEMPT

In what other ways did you add value to the fund?

Careful selection of attractively priced securities was the main vehicle we used
to enhance the fund's returns. Along those lines, we sold some California GOs at
a profit and used the proceeds to purchase  lower-rated  New York COPs and lease
agreements that we felt were attractively valued. However,  nationally improving
credit  conditions  made such securities  difficult to find.  That's because the
yield spread--or interest rate difference--between comparable-maturity municipal
securities  with  different  credit  ratings  continued to decrease as investors
reached for higher  yields.  Thanks in part to our strong credit  research team,
however,  we  were  able to find  many  securities  that  were  undervalued  and
subsequently appreciated in price.

What impact did the federal budget agreement have on the municipal market?

Not much.  While a strong  budget  deal could  have  sparked a bond  rally,  the
version that passed failed to have that effect. Although steps toward a balanced
budget are  generally  positive for the bond market,  the recent accord fails to
deal with two very  controversial  issues,  Medicare and Social  Security.  As a
result,  the positive impact of Congress  reaching an agreement was muted by the
realization  that critical  steps are still needed if our economy is to gain any
long-term benefits from a budget plan.

The most  interesting  part of the agreement will likely be the type of tax cuts
that are finally  ratified.  If a strong capital gains cut is set into place, it
could have a negative  impact on bonds,  as a lower capital gains tax rate would
increase the after-tax returns of stocks.

In July, fund  shareholders  will be voting on a proposal to merge the fund with
the Benham Intermediate-Term Tax-Free fund. If this merger is approved, how will
it affect the fund's management?

Shareholders will see no change to the fund's management.  The new combined fund
will retain all of this fund's  investment  objectives  and  policies,  so we'll
continue to manage the new fund in the same way we've managed this one. The only
significant  difference is that the new fund will have lower management fees and
expenses.

TOP FIVE STATES (% of fund investments)
                 As of                      As of
                 4/30/97                  10/31/96
New York           16%      New York         14%
Texas              13%      Texas            12%
Pennsylvania       11%      Massachusetts    10%
Massachusetts      10%      Pennsylvania     10%
Ohio                7%      Ohio              8%

[pie charts]

PORTFOLIO  COMPOSITION BY SECURITY TYPE (as of 4/30/97) 
Revenue Bonds 67% 
GO 17%
COPs/Leases 14% 
Prerefunded/ETM 2%

PORTFOLIO COMPOSITION BY SECURITY TYPE (as of 10/31/96) 
Revenue Bonds 68% 
GO 16%
COPs/Leases 12% 
Prerefunded/ETM 4%


Semiannual Report                              Intermediate-Term Tax-Exempt   13


                          INTERMEDIATE-TERM TAX-EXEMPT

What is your outlook for the municipal market over the next six months?

Bond yields rose during the first four months of 1997,  largely because the U.S.
economy showed faster-than-normal growth and wages rose. While these factors led
the Federal Reserve (the Fed) to raise  short-term  interest rates in March, the
recent  moderating  trend of economic  growth  allowed the Fed to hold  interest
rates steady after its May meeting.  Whether the Fed will  continue to stand pat
or decide to raise rates again soon is uncertain.  Current  economic  conditions
suggest that inflation can remain tame even as the economy flourishes.

As such, we believe that the Fed should not need to raise rates  dramatically to
keep inflation within  reasonable  levels.  If U.S. economic growth slows of its
own accord, municipal securities could rally; but with wage pressures increasing
the threat of a Fed rate hike, any signs of an  overheating  economy will likely
push municipal bond prices lower.

Another development we will monitor closely is the relative  performance between
municipal  and  Treasury  securities  (see  page  3).  Lately,  municipals  have
significantly  outperformed  Treasurys, a situation caused in part by relatively
low municipal  issuance.  Although municipal issuance should remain fairly light
in the near future,  the  likelihood  that  municipal  bonds will  continue this
outperformance is  diminishing--their  prices have reached levels where they are
considered  historically  expensive  compared with like-maturity  Treasurys.  If
municipals  continue this trend,  investor demand could eventually shift back to
Treasurys, removing a key supporting factor for municipal bond prices.

With this outlook in mind, what are your plans for the fund going forward?

Currently,  the market  seems to expect that  economic  growth will  continue to
slow, allowing the Fed to hold short-term rates steady; however, we are inclined
to somewhat  disagree  with that notion.  As such,  we will likely  maintain the
fund's  bullet  structure  for now as an added  precaution  in case  rates  move
sharply  higher or lower.  If the  economic  outlook  changes  dramatically,  we
believe that this position will allow us to respond appropriately.  We will also
continue  to utilize our credit  research  team to look for  securities  that we
believe will add value to the fund's returns.

[pie charts]

PORTFOLIO COMPOSITION BY CREDIT RATING (as of 4/30/97)
AAA 76%
AA 10%
A 6%
BBB 8%

PORTFOLIO COMPOSITION BY CREDIT RATING (as of 10/31/96)
AAA 75%
AA 9%
A 11%
BBB 5%


14   Intermediate-Term Tax-Exempt                   American Century Investments


                            SCHEDULE OF INVESTMENTS
                          INTERMEDIATE-TERM TAX-EXEMPT

APRIL 30, 1997 (UNAUDITED)


Principal Amount                ($ in Thousands)                        Value
- --------------------------------------------------------------------------------

MUNICIPAL SECURITIES
Arizona--1.0%
$       750   Maricopa County Certificates of
                Participation, 5.625%, 6/1/00                        $  761
                                                                     ------
Colorado--1.5%
      1,000   Denver Sales Tax Rev., Series A,
                (Major League Baseball Stadium
                District), 6.10%, 10/1/01
                (FGIC)                                                1,055
                                                                     ------
District of Columbia--1.4%
      1,000   District of Columbia Hospital Rev.,
                Series A, (Medlantic Health Care
                Group), 5.25%, 8/15/02 (MBIA)                         1,014
                                                                     ------
Florida--1.5%
      1,000   Lakeland Electric and Water Rev.,
                Series B, 6.00%, 10/1/09
                (FGIC)                                                1,072
                                                                     ------
Georgia--3.7%
      1,000   Atlanta Airport Facilities Rev.,
                7.00%, 1/1/01                                         1,067
        500   Georgia State GO, Series B, 6.30%,
                3/1/08                                                  551
      1,000   Metropolitan Atlanta Rapid Transit
                Auth. Sales Tax Rev., Series M,
                6.05%, 7/1/01                                         1,046
                                                                     ------
                                                                      2,664
                                                                     ------
Illinois--6.1%
      2,000   Chicago O'Hare International
                Airport Rev., Series A, 5.00%,
                1/1/00 (MBIA)                                         2,009
      2,250   Illinois State GO, 6.00%, 10/1/01                       2,353
                                                                     ------
                                                                      4,362
                                                                     ------
Massachusetts--9.9%
      2,605   Massachusetts Bay Transportation
                Auth.  Rev., Series C, 5.40%,
                3/1/00                                                2,656
      2,000   Massachusetts Housing Finance
                Agency Rev., Series A, 5.90%,
                1/1/03 (AMBAC)                                        2,068

Principal Amount                ($ in Thousands)                        Value
- --------------------------------------------------------------------------------

$     1,500   Massachusetts State GO, Series A,
                (Consolidated Loan), 5.00%,
                3/1/06 (AMBAC)                                       $1,492
      1,000   Massachusetts State GO, Series D,
                (Consolidated Loan), 5.00%,
                11/1/16 (AMBAC)                                         921
                                                                     ------
                                                                      7,137
                                                                     ------
Mississippi--2.8%
      2,000   Mississippi Hospital Equipment and
                Facilities Auth. Rev., (North Miss.
                Health Service), 5.00%,
                5/15/00 (AMBAC)                                       2,016
                                                                     ------
Missouri--1.5%
      1,000   Missouri Board of Public Buildings
                State Office Buildings Special
                Obligation Rev., 6.30%,
                12/1/05                                               1,063
                                                                     ------
Nebraska--2.9%
      2,000   Nebraska Investment Finance
                Auth. Hospital Rev., (Methodist
                Health System), 6.55%, 3/1/99
                (MBIA)                                                2,072
                                                                     ------
New Jersey--6.5%
      1,030   Atlantic City Board of Education
                GO, 6.00%, 12/1/06 (AMBAC)                            1,089
      1,410   New Jersey Educational Facility
                Auth. Rev., Series A, (New Jersey
                Institute of Technology), 5.90%,
                7/1/08 (MBIA)                                         1,486
      1,000   New Jersey Health Care Facilities
                Financing Auth. Rev., (Atlantic
                City Medical Center), 6.15%,
                7/1/99                                                1,027
      1,000   New Jersey State Turnpike Auth.
                Rev., Series A, 6.20%, 1/1/00                         1,035
                                                                     ------
                                                                      4,637
                                                                     ------
New York--16.2%
      1,950   City University of New York
                Certificates of Participation,
                (John Jay College), 5.00%,
                8/15/09 (AMBAC)                                       1,880
      2,500   Nassau County, Series T, 5.20%,
                9/1/05 (FGIC)                                         2,526

See Notes to Financial Statements


Semiannual Report                              Intermediate-Term Tax-Exempt   15


                            SCHEDULE OF INVESTMENTS
                          INTERMEDIATE-TERM TAX-EXEMPT

APRIL 30, 1997 (UNAUDITED)

Principal Amount                ($ in Thousands)                        Value
- --------------------------------------------------------------------------------

$     1,500   New York State Dorm. Auth. Rev.,
                Series A, 6.50%, 5/15/04                           $  1,595
      1,000   New York State Dorm. Auth. Rev.,
                Series A, 6.50%, 5/15/06                              1,067
      1,125   New York State Medical Care
                Facilities Finance Agency Rev.,
                (Hospital and Nursing Home),
                5.95%, 8/15/09 (FHA)                                  1,149
      1,160   New York State Thruway Auth. Rev.,
                (Service Contract), 5.50%,
                4/1/06                                                1,157
      1,000   New York State Thruway Auth. Rev.,
                Series B, 5.125%, 4/1/15
                (MBIA)                                                  939
      1,260   New York State Urban
                Development Corp. Rev.,
                (Correctional Facilities), 5.40%,
                1/1/06 (AMBAC)                                        1,284
                                                                     ------
                                                                     11,597
                                                                     ------
Ohio--6.7%
      1,200   Ohio Higher Educational Facility
                Commission Rev., (University of
                Dayton), 5.55%, 12/1/07 (FGIC)                        1,234
      3,320   Ohio Water Development Auth.
                Pollution Control Facilities Rev.,
                6.00%, 12/1/05 (MBIA)                                 3,541
                                                                     ------
                                                                      4,775
                                                                     ------
Oregon--4.2%
      1,805   Lane County School District No. 19
                GO, (Springfield), 6.375%,
                10/15/05 (MBIA)                                       1,970
      1,000   Oregon State Department
                Transportation Rev., 5.50%,
                6/1/00 (MBIA)                                         1,026
                                                                     ------
                                                                      2,996
                                                                     ------
Pennsylvania--10.6%
      1,000   Harrisburg Auth. Lease Rev.,
                6.25%, 6/1/00 (FSA)(1)                                1,044
      1,500   Pennsylvania Turnpike Commission
                Rev., Series L, 6.25%, 6/1/01
                (AMBAC)                                               1,582

Principal Amount                ($ in Thousands)                        Value
- --------------------------------------------------------------------------------

$     2,000   Philadelphia Gas Works Rev., 14th
                Series, 5.70%, 7/1/00 (FSA)                          $2,060
      2,000   Philadelphia Water & Wastewater
                Rev., 5.15%, 6/15/04 (FGIC)                           1,999
      1,000   Philadelphia Water & Wastewater
                Rev., 5.00%, 6/15/12 (FGIC)                             939
                                                                     ------
                                                                      7,624
                                                                     ------
Texas--12.6%
      2,000   Brazos Higher Education Auth.
                Rev., Series A-1, 5.50%,
                12/1/98                                               2,039
      1,875   Brownsville Utility System Rev.,
                6.00%, 9/1/08 (AMBAC)                                 1,995
      1,000   Dallas-Fort Worth Regional Airport
                Rev., Series A, 5.90%, 11/1/08
                (MBIA)                                                1,038
      1,340   Harris County Health Facilities
                Development Corp. Hospital Rev.,
                (St. Luke's Episcopal Hospital),
                6.40%, 2/15/00                                        1,394
      1,000   Tarrant County Health Facility
                Development Corporation Health
                System Rev., (Harris Methodist
                Health System), 5.00%, 9/1/07
                (AMBAC)                                                 979
      1,500   Texas State Public Finance Auth.
                Building Rev., (Technical College),
                6.25%, 8/1/09 (MBIA)                                  1,632
                                                                     ------
                                                                      9,077
                                                                     ------
Utah--1.5%
      1,000   Salt Lake County Municipal
                Building Auth. Lease Rev., Series
                A, 6.00%, 10/1/07 (MBIA)                              1,056
                                                                     ------
Virginia--1.9%
      1,275   Metropolitan Washington D.C.
                Airports Auth. Rev., Series A,
                6.30%, 10/1/03 (MBIA)                                 1,361
                                                                     ------

See Notes to Financial Statements


16   Intermediate-Term Tax-Exempt                   American Century Investments


                            SCHEDULE OF INVESTMENTS
                          INTERMEDIATE-TERM TAX-EXEMPT

APRIL 30, 1997 (UNAUDITED)

Principal Amount                ($ in Thousands)                        Value
- --------------------------------------------------------------------------------

Washington--3.7%
$       500   Snohomish County School District
                GO, (Edmonds School District
                No. 15), 6.00%, 6/1/06 (FGIC)                      $    530
      1,000   Tacoma Electric System Rev.,
                6.10%, 1/1/07 (FGIC)                                  1,060
      1,000   Washington State Public Power
                Supply Rev., Series C, (Project 2),
                7.30%, 7/1/00                                         1,069
                                                                     ------
                                                                      2,659
                                                                     ------
West Virginia--1.5%
      1,090   West Virginia State GO, Series D,
                5.00%, 11/1/10 (FGIC)                                 1,052
                                                                     ------
Wisconsin--2.3%
      1,590   Wisconsin State Health and
                Educational Facility Auth. Rev.,
                (Aurora Medical Group), 6.00%,
                11/15/10 (FSA)                                        1,679
                                                                     ------

TOTAL INVESTMENT SECURITIES--100.0%                                 $71,729
   (Cost $70,586)                                                   =======

Notes to Schedule of Investments 
AMBAC = AMBAC Indemnity Corp.
FGIC = Financial  Guaranty Insurance Company 
FHA = Federal Housing Authority 
FSA = Financial Security Association 
GO = General Obligation 
MBIA = Municipal Bond Insurance Association 
(1) Escrowed in U.S. Government Securities.

See Notes to Financial Statements


Semiannual Report                              Intermediate-Term Tax-Exempt   17

<TABLE>
<CAPTION>
                              LONG-TERM TAX-EXEMPT

                                             30-Day                  30-Day Tax-Equivalent Yields
                                               SEC           28%           31%           36%           39.6%
                                              Yield      Tax Bracket   Tax Bracket   Tax Bracket    Tax Bracket

CURRENT YIELDS AS OF APRIL 30, 1997
<S>                                           <C>           <C>           <C>           <C>            <C>  
Long-Term Tax-Exempt                          5.00%         6.94%         7.25%         7.81%          8.28%

                                                                        AVERAGE ANNUAL RETURNS
                                            6 MONTHS       1 YEAR        3 YEARS       5 YEARS       10 YEARS
TOTAL RETURNS AS OF APRIL 30, 1997
Long-Term Tax-Exempt .......................  1.63%         7.10%         6.77%         6.73%          7.66%
Lehman Long-Term Municipal Bond Index ......  1.86%         7.99%         8.19%         7.95%          9.07%
Average General Municipal
Debt Fund(1) ...............................  1.68%         6.13%         6.28%         6.65%          7.62%
Fund's Ranking Among General
Municipal Debt Funds(1) ....................   --       37 out of 231 48 out of 170 46 out of 105  34 out of 67

(1)  According to Lipper Analytical Services.
</TABLE>

See pages 36-37 for more information  about returns,  the comparative  index and
Lipper fund rankings.


[mountain graph - data below]

GROWTH OF $10,000 OVER TEN YEARS

Value on 4/30/97

Long-Term Tax-Exempt                $20,924
Lehman Long-Term Municipal Index    $23,832

            Long-Term Tax-Exempt   Lehman Long-Term Municipal Index
Apr-87            $10,000                      $10,000
Jun-87            $10,120                      $10,205
Sep-87             $9,715                       $9,922
Dec-87            $10,427                      $10,373
Mar-88            $10,684                      $10,758
Jun-88            $10,890                      $11,065
Sep-88            $11,190                      $11,437
Dec-88            $11,507                      $11,773
Mar-89            $11,557                      $11,891
Jun-89            $12,246                      $12,714
Sep-89            $12,140                      $12,647
Dec-89            $12,605                      $13,183
Mar-90            $12,512                      $13,210
Jun-90            $12,832                      $13,550
Sep-90            $12,719                      $13,440
Dec-90            $13,382                      $14,135
Mar-91            $13,588                      $14,460
Jun-91            $13,816                      $14,829
Sep-91            $14,388                      $15,496
Dec-91            $14,990                      $16,051
Mar-92            $15,003                      $16,107
Jun-92            $15,572                      $16,817
Sep-92            $15,961                      $17,277
Dec-92            $16,130                      $17,693
Mar-93            $16,708                      $18,464
Jun-93            $17,232                      $19,227
Sep-93            $17,848                      $19,996
Dec-93            $18,090                      $20,302
Mar-94            $17,103                      $18,674
Jun-94            $17,217                      $18,808
Sep-94            $17,324                      $18,885
Dec-94            $17,080                      $18,455
Mar-95            $18,221                      $20,293
Jun-95            $18,603                      $20,758
Sep-95            $19,120                      $21,324
Dec-95            $20,239                      $22,753
Mar-96            $19,682                      $22,159
Jun-96            $19,763                      $22,421
Sep-96            $20,346                      $23,116
Dec-96            $20,865                      $23,758
Mar-97            $20,717                      $23,554
Apr-97            $20,924                      $23,832

Past  performance  does not  guarantee  future  results.  Investment  return and
principal  value will fluctuate,  and redemption  value may be more or less than
original cost. The line representing the fund's total return includes  operating
expenses (such as transaction  costs and management  fees) that reduce  returns,
while the total return line of the index does not.

PORTFOLIO AT A GLANCE
                                 4/30/97         10/31/96
Number of Securities               50               55
Weighted Average Maturity      18.0 years       17.8 years
Average Duration                8.3 years        8.3 years
Expense Ratio                    0.60%*            0.59%

* Annualized.


18   Long-Term Tax-Exempt                           American Century Investments


                              LONG-TERM TAX-EXEMPT

Management Q & A

An inverview  with Dave MacEwen,  a senior  municipal  portfolio  manager on the
Tax-Exempt funds management team.

How did the fund perform?

The fund's return reflects the bearish bond  environment  that prevailed  during
the first four months of 1997.  For the  six-month  period ended April 30, 1997,
the fund's total return of 1.63% essentially matched the 1.68% average return of
the 231 funds in Lipper's  "General  Municipal Debt Funds" category and slightly
trailed the 1.86% return of the fund's benchmark.

However,  the fund's  one-year  return of 7.10%  placed it in the top 20% of its
peer group.  This return  reflected  the more  bullish  conditions  that were in
evidence during mid-1996.  (See the Total Returns table on the previous page for
other fund performance comparisons.)

Did you change the fund's positioning during the period?

We made only  slight  adjustments  to the  fund.  Choosing  a more  conservative
approach,  we maintained the fund's duration in a relatively narrow range around
8 years.  Since long-term  municipal bond rates fluctuated  mildly compared with
other  maturity  sectors,  we felt the best  strategy  was to maintain a neutral
duration relative to our peers.

[bar charts - data below]

LONG-TERM  TAX-EXEMPT'S  ONE-YEAR  RETURNS FOR THE PAST TEN YEARS (Periods ended
April 30)

          Long-Term Tax-Exempt   Lehman Long-Term Municipal Index

4/30/88           6.89%                        8.43%
4/30/89          10.99%                       12.89%
4/30/90           3.35%                        6.62%
4/30/91          12.51%                       12.52%
4/30/92           9.55%                       10.73%
4/30/93          11.65%                       15.11%
4/30/94           1.89%                        0.54%
4/30/95           6.14%                        7.78%
4/30/96           7.09%                        8.80%
4/30/97           7.10%                        7.99%

This graph  illustrates  the fund's  returns over the past 10 years and compares
them with the  index's  returns.  The fund's  total  returns  include  operating
expenses, while the index's do not. See page 36 for a definition of the index.


Semiannual Report                                      Long-Term Tax-Exempt   19


                              LONG-TERM TAX-EXEMPT


What techniques did you use to add value to the fund?

Careful selection of attractively priced securities was the main vehicle we used
to enhance the fund's returns.  However,  nationally improving credit conditions
made this task  difficult.  That's  because the yield  spread--or  interest rate
difference--between  comparable-maturity  municipal  securities  with  different
credit  ratings  continued to decrease as investors  reached for higher  yields.
Thanks in part to our strong  credit  research  team,  we were able to find many
securities that were undervalued and subsequently appreciated in price.

Can you cite an example?

Several times during the period,  we purchased New York  municipal  issues rated
BBB that became available at attractive  prices.  While a trend toward narrowing
yield spreads has made it difficult to locate  lower-rated  municipals that pass
our  close   scrutiny,   the  New  York  municipal   market  still  offers  some
opportunities.  New York still has some welfare  issues to contend with, but the
state's generally  improving  economy helped make these municipals  particularly
attractive  choices.  We  sold  many  of them  at a  substantial  profit.  These
undervalued,  lower-rated  bonds had the added  attraction of buoying the fund's
yield.

What impact did the federal budget agreement have on the municipal market?

Not much.  While a strong  budget  deal could  have  sparked a bond  rally,  the
version that passed failed to have that effect. Although steps toward a balanced
budget are  generally  positive for the bond market,  the recent accord fails to
deal with two very  controversial  issues,  Medicare and Social  Security.  As a
result,  the positive impact of Congress  reaching an agreement was muted by the
realization  that critical  steps are still needed if our economy is to gain any
long-term benefits from a budget plan.

The most  interesting  part of the agreement will likely be the type of tax cuts
that are finally  ratified.  If a strong capital gains cut is set into place, it
could have a negative  impact on bonds,  as a lower capital gains tax rate would
increase the after-tax returns of stocks.

In July, fund  shareholders  will be voting on a proposal to merge the fund with
the Benham  Long-Term  Tax-Free  fund.  If this merger is approved,  how will it
affect the fund's management?

Shareholders will see no change to the fund's management.  The new combined fund
will retain all of this fund's investment objectives and policies, so


TOP FIVE STATES (% of fund investments)
                 As of                      As of
                 4/30/97                  10/31/96
California         18%      California       20%
New York           15%      New York         12%
Illinois           12%      Illinois          9%
Texas              11%      Texas             8%
Massachusetts       6%      Massachusetts     7%

[pie charts]

PORTFOLIO  COMPOSITION BY SECURITY TYPE (as of 4/30/97) 
Revenue Bonds 60% 
GO 18%
COPs/Leases 13% 
Land-Secured 5% 
Prerefunded/ETM 4%

PORTFOLIO COMPOSITION BY SECURITY TYPE (as of 10/31/96) 
Revenue Bonds 61% 
GO 16%
COPs/Leases 12% 
Prerefunded/ETM 7% 
Land-Secured 4%


20   Long-Term Tax-Exempt                           American Century Investments


                              LONG-TERM TAX-EXEMPT

we'll  continue to manage the new fund in the same way we've  managed  this one.
The only significant  difference is that the new fund will have lower management
fees and expenses.

What is your outlook for the municipal market over the next six months?

Bond yields rose during the first four months of 1997,  largely because the U.S.
economy showed faster-than-normal growth and wages rose. While these factors led
the Federal Reserve (the Fed) to raise  short-term  interest rates in March, the
recent  moderating  trend of economic  growth  allowed the Fed to hold  interest
rates steady after its May meeting.  Whether the Fed will  continue to stand pat
or decide to raise rates again soon is uncertain.  Current  economic  conditions
suggest that inflation can remain tame even as the economy flourishes.

As such, we believe that the Fed should not need to raise rates  dramatically to
keep inflation within  reasonable  levels.  If U.S. economic growth slows of its
own accord, municipal securities could rally; but with wage pressures increasing
the threat of a Fed rate hike, any signs of an  overheating  economy will likely
push municipal bond prices lower.

Another development we will monitor closely is the relative  performance between
municipal  and  Treasury  securities  (see  page  3).  Lately,  municipals  have
significantly  outperformed  Treasurys, a situation caused in part by relatively
low municipal  issuance.  Although municipal issuance should remain fairly light
in the near future,  the  likelihood  that  municipal  bonds will  continue this
outperformance is  diminishing--their  prices have reached levels where they are
considered  historically  expensive  compared with like-maturity  Treasurys.  If
municipals  continue this trend,  investor demand could eventually shift back to
Treasurys, removing a key supporting factor for municipal bond prices.

With this outlook in mind, what are your plans for the fund going forward?

Currently,  the market  seems to expect that  economic  growth will  continue to
slow, allowing the Fed to hold short-term rates steady; however, we are inclined
to  somewhat  disagree  with  that  notion.  As such,  we are  keeping  the fund
conservatively positioned, with its duration slightly shorter than the durations
of its peers as an added  precaution  in case  rates  continue  to rise.  If the
economic outlook changes dramatically,  we believe that this position will allow
the fund to respond  appropriately.  We will also continue to utilize our credit
research  team to look for  securities  that we  believe  will add  value to the
fund's returns.

[pie charts]

PORTFOLIO COMPOSITION BY CREDIT RATING (as of 4/30/97)
AAA 54%
AA 24%
A 9%
BBB 13%

PORTFOLIO COMPOSITION BY CREDIT RATING (as of 10/31/96)
AAA 54%
AA 24%
A 12%
BBB 10%


Semiannual Report                                      Long-Term Tax-Exempt   21

                            SCHEDULE OF INVESTMENTS
                              LONG-TERM TAX-EXEMPT

APRIL 30, 1997 (UNAUDITED)

Principal Amount                ($ in Thousands)                        Value
- --------------------------------------------------------------------------------

MUNICIPAL SECURITIES
Alaska--0.1%
$        40   Alaska State Housing Finance
                Corp Rev., Series B, 8.75%,
                12/1/16 (LOC: Swiss Bank)                           $    41
                                                                    -------
California--18.4%
      2,000   California State Public Works Lease
                Rev., (Department of Corrections
                Prisons A), 5.00%, 12/1/19
                (AMBAC)                                               1,834
      1,000   California State Public Works
                Lease Rev., (University Project A),
                6.20%, 10/1/08                                        1,061
      1,225   Long Beach Water Rev., 6.125%,
                5/1/19                                                1,260
      1,500   Los Angeles Community
                Redevelopment Agency Rev.,
                (Bunker Hill), 6.50%, 12/1/14
                (FSA)                                                 1,618
      1,500   Metropolitan Water District Rev.,
                Series A, (Southern California),
                5.75%, 7/1/21                                         1,532
      1,850   Northern California Power Agency
                Rev., Series A, (Hydroelectric
                Project #1), 6.25%, 7/1/12
                (MBIA)                                                1,941
      1,000   San Jose Redevelopment Agency
                Tax Allocation, Series D, 5.75%,
                8/1/24                                                  992
                                                                    -------
                                                                     10,238
                                                                    -------
Colorado--0.6%
        300   Colorado Housing Finance Auth.
                Rev., Series C, (Single Family
                Residential), 8.70%, 9/1/07                             311
                                                                    -------
Connecticut--5.5%
      1,000   Connecticut GO, Series E, 6.00%,
                3/15/12                                               1,060
      1,880   Connecticut State Development
                Auth. Rev., Series A, 6.375%,
                10/15/24                                              2,005
                                                                    -------
                                                                      3,065
                                                                    -------

Principal Amount                ($ in Thousands)                        Value
- --------------------------------------------------------------------------------

Florida--2.5%
$     1,350   Tampa Sports Auth. Sales Tax Rev.,
                (Tampa Bay Arena Project),
                5.75%, 10/1/25 (MBIA)                                $1,380
                                                                    -------
Illinois--11.7%
      1,000   City of Chicago Rev., (Peoples Gas,
                Light and Coke Co.), 7.50%,
                3/1/15                                                1,080
      1,000   Cook County GO, 7.00%,
                11/1/10, Prerefunded 11/1/00
                at 102% of Par (MBIA)(1)                              1,093
        500   Illinois Dedicated Tax Rev., (Civic
                Center), 6.25%, 12/15/20
                (AMBAC)                                                 535
      1,000   Illinois Development Finance Auth.
                Waste Disposal Rev., (Armstrong
                World Industries Project), 5.95%,
                12/1/24                                                 982
      1,500   Illinois GO, 6.25%, 10/1/06                             1,595
      1,000   Illinois Regional Transportation
                Auth. Rev., Series A, 7.20%,
                11/1/20 (AMBAC)                                       1,192
                                                                    -------
                                                                      6,477
                                                                    -------
Kansas--1.9%
      1,000   Kansas City Utility System Rev.,
                6.375%, 9/1/23 (FGIC)                                 1,061
                                                                    -------
Kentucky--2.5%
      1,000   Carroll County Pollution Control
                Rev., Series A, (Kentucky Utilities
                Company Project), 7.45%,
                9/15/16                                               1,117
        255   Kentucky Housing Corp. Rev.,
                Series C, 7.90%, 1/1/21 (FHA)                           267
                                                                    -------
                                                                      1,384
                                                                    -------
Massachusetts--6.2%
      1,000   Boston GO, Series B, 5.875%,
                8/1/12 (AMBAC)                                        1,024
      1,000   Boston GO, Series B, 5.875%,
                8/1/13 (AMBAC)                                        1,020
      1,500   Massachusetts Bay Transit Auth.
                Rev., Series A, 5.50%, 3/1/22
                (MBIA)                                                1,431
                                                                    -------
                                                                      3,475
                                                                    -------

See Notes to Financial Statements


22   Long-Term Tax-Exempt                           American Century Investments


                            SCHEDULE OF INVESTMENTS
                              LONG-TERM TAX-EXEMPT

APRIL 30, 1997 (UNAUDITED)

Principal Amount                ($ in Thousands)                        Value
- --------------------------------------------------------------------------------

Michigan--2.5%
$     1,500   Detroit Sewer Disposal Rev., Series
                B, 5.25%, 7/1/21 (MBIA)                              $1,396
                                                                    -------
New York--15.3%
      1,000   Municipal Assistance Corp. Rev.,
                Series 67, 7.625%, 7/1/08                             1,082
      2,500   New York City GO, Series I, 6.25%,
                4/15/27                                               2,498
      1,000   New York Local Government
                Assistance Corp. Rev., Series D,
                6.75%, 4/1/07                                         1,100
      1,000   New York State Environmental
                Facilities Corp. Pollution Control
                Rev., Series E, 6.30%, 6/15/02                        1,063
      1,000   New York State Urban
                Development Corp. Rev., Series
                4, (Correctional Facilities),
                5.375%, 1/1/23                                          900
      2,000   New York State Urban
                Development Corp. Rev., Series
                6, (Correctional Facilities),
                5.375%, 1/1/15                                        1,860
                                                                    -------
                                                                      8,503
                                                                    -------
North Carolina--3.0%
        520   North Carolina Eastern Municipal
                Power Agency System Rev.,
                Series A, 7.50%, 1/1/10,
                Prerefunded 1/1/09 at 100%
                of Par(1)                                               618
      1,000   North Carolina Municipal Power
                Agency #1 Rev., (Catawba
                Electric), 6.00%, 1/1/10 (MBIA)                       1,063
                                                                    -------
                                                                      1,681
                                                                    -------
Ohio--2.4%
        750   Ohio Higher Educational Facility
                Commission Rev., (Case Western
                Reserve University), 6.50%,
                10/1/20                                                 821
        500   Ohio Higher Educational Facility
                Commission Rev., (University of
                Dayton), 5.80%, 12/1/14
                (FGIC)                                                  505
                                                                    -------
                                                                      1,326
                                                                    -------

Principal Amount                ($ in Thousands)                        Value
- --------------------------------------------------------------------------------

Pennsylvania--3.5%
$     1,000   Philadelphia Gas Works Rev., 15th
                Series, 5.375%, 8/1/07 (FSA)                         $1,010
      1,000   Philadelphia Water & Wastewater
                Rev., 5.25%, 6/15/23 (MBIA)                             921
                                                                    -------
                                                                      1,931
                                                                    -------
Puerto Rico--0.9%
        500   Puerto Rico Commonwealth GO,
                6.45%, 7/1/17                                           529
                                                                    -------
Rhode Island--4.3%
      1,000   Rhode Island Depositors Economic
                Protection Corp. Special
                Obligation Rev., Series A, 6.25%,
                8/1/16 (MBIA)                                         1,068
      1,300   Rhode Island Depositors Economic
                Protection Corp. Special
                Obligation Rev., Series B, 6.00%,
                8/1/17 (MBIA)                                         1,308
                                                                    -------
                                                                      2,376
                                                                    -------
Texas--10.5%
      1,000   Alliance Airport Auth. Special
                Facilities Rev., (American Airlines
                Project), 7.00%, 12/1/11                              1,107
      1,000   Denison Hospital Auth. Rev.
                (Texoma Medical Center Income
                Project), 6.125%, 8/15/12                             1,000
      1,000   Denton Utility System Rev., Series
                A, 5.95%, 12/1/14 (MBIA)                              1,024
      2,500   Texas Municipal Power Agency Rev.,
                Series A, 6.75%, 9/1/12
                (AMBAC)                                               2,701
                                                                    -------
                                                                      5,832
                                                                    -------
Virginia--2.9%
      1,000   Metropolitan Area Transportation
                Auth. Rev., 6.00%, 7/1/10
                (FGIC)                                                1,063
        500   Norfolk Hospital Development Auth.
                Rev., (Children's Hospital), 7.00%,
                6/1/11, Prerefunded 6/1/01 at
                102% of Par (AMBAC)(1)                                  550
                                                                    -------
                                                                      1,613
                                                                    -------

See Notes to Financial Statements


Semiannual Report                                      Long-Term Tax-Exempt   23


                            SCHEDULE OF INVESTMENTS
                              LONG-TERM TAX-EXEMPT

APRIL 30, 1997 (UNAUDITED)

Principal Amount                ($ in Thousands)                        Value
- --------------------------------------------------------------------------------

Washington--1.8%
$     1,000   Washington State Public Power
                Supply Rev., Series A, (Nuclear
                Project #1), 5.75%, 7/1/12
                (MBIA)                                             $  1,000
                                                                    -------
Wisconsin--2.3%
      1,180   Winneconne Community School
                District GO, 6.75%, 4/1/14
                (FGIC)                                                1,286
                                                                    -------
Wyoming--0.4%
        205   Wyoming Community Development
                Auth. Rev., Series B, (Single
                Family Mortgage), 8.125%,
                6/1/21 (FHA)                                            211
                                                                    -------

TOTAL MUNICIPAL SECURITIES--99.2%                                    55,116
   (Cost $52,988)                                                   -------

SHORT-TERM MUNICIPAL SECURITIES--0.7%
        400   Chicago O'Hare International
                Airport Rev., VRDN, 3.85%,
                5/1/97 (LOC: Credit Suisse)                             400
                                                                    -------
   (Cost $400)

TEMPORARY CASH INVESTMENTS--0.1%
    45,000    Units of Participation in
                Chase Vista Tax Free Fund
                (Institutional Shares)                                   45
                                                                    -------
   (Cost $45)
TOTAL INVESTMENT SECURITIES--100.0%                                 $55,561
   (Cost $53,433)                                                   =======

Notes to Schedules of Investments 
AMBAC = AMBAC Indemnity Corp.
FGIC = Financial Guaranty Insurance Company 
FHA = Federal Housing Authority 
FSA = Financial Security Association 
GO = General Obligation 
LOC = Letter of Credit
MBIA = Municipal Bond Insurance Association

resets = The frequency  with which a  fixed-income  security's  coupon  changes,
based on current market conditions or an underlying index. The more frequently a
security resets,  the less risk the investor is taking that the coupon will vary
significantly from current market rates.

VRDN = Variable Rate Demand Note.  Interest  reset date is indicated and used in
calculating the weighted  average  portfolio  maturity.  Rate shown is effective
4/30/97.

(1) Escrowed in U.S. Government Securities.

See Notes to Financial Statements


24   Long-Term Tax-Exempt                           American Century Investments


<TABLE>
<CAPTION>
                      STATEMENTS OF ASSETS AND LIABILITIES

APRIL 30, 1997 (UNAUDITED)

                                                                 LIMITED-TERM   INTERMEDIATE-TERM     LONG-TERM
                                                                  TAX-EXEMPT       TAX-EXEMPT        TAX-EXEMPT

                                                              ($ and Shares in Thousands Except Per-Share Amounts)
ASSETS
<S>                                                                     <C>            <C>                <C>
Investment securities, at value (identified cost of
  $46,419, $70,586 and $53,433, respectively) (Note 3) .......      $46,372          $71,729          $55,561
Cash .........................................................           --               --               20
Receivable for investments sold ..............................           --              382               --
Interest receivable ..........................................          604            1,147              851
                                                                     ------           ------           ------
                                                                     46,976           73,258           56,432
                                                                     ------           ------           ------

LIABILITIES
Disbursements in excess of demand deposit cash ...............          185              488               96
Payable for investments purchased ............................          997              525               --
Payable for capital shares redeemed ..........................          150               --                3
Dividends payable ............................................           26               47               40
Accrued management fees (Note 2) .............................           23               36               27
                                                                     ------           ------           ------
                                                                      1,381            1,096              166
                                                                     ------           ------           ------
Net Assets Applicable to Outstanding Shares ..................      $45,595          $72,162          $56,266
                                                                    =======          =======          =======

CAPITAL SHARES, $0.01 PAR VALUE
Authorized ...................................................      200,000          200,000          200,000
                                                                    =======          =======          =======
Outstanding ..................................................        4,552            7,049            5,368
                                                                      =====            =====            =====
Net Asset Value Per Share ....................................       $10.02           $10.24           $10.48
                                                                     ======           ======           ======

NET ASSETS CONSIST OF:
Capital (par value and paid in surplus) ......................      $45,465          $70,780          $53,856
Accumulated undistributed net realized gain
  from investment transactions ...............................          177              239              282
Net unrealized appreciation (depreciation)
  on investments (Note 3) ....................................          (47)           1,143            2,128
                                                                     ------           ------           ------
                                                                    $45,595          $72,162          $56,266
                                                                    =======          =======          =======
</TABLE>

See Notes to Financial Statements


Semiannual Report                      Statements of Assets and Liabilities   25

<TABLE>
<CAPTION>
                            STATEMENTS OF OPERATIONS

For the Six Months Ended april 30, 1997 (Unaudited)

                                                                 LIMITED-TERM   INTERMEDIATE-TERM     LONG-TERM
                                                                  TAX-EXEMPT       TAX-EXEMPT        TAX-EXEMPT

                                                              ($ and Shares in Thousands Except Per-Share Amounts)
INVESTMENT INCOME
Income:
<S>                                                                  <C>              <C>             <C>   
Interest .........................................................   $1,126           $2,028          $1,691
                                                                     ------           ------          ------
Expenses:
Management fees (Note 2) .........................................      145              230             175
                                                                     ------           ------          ------
Net investment income ............................................      981            1,798           1,516
                                                                     ------           ------          ------

REALIZED AND UNREALIZED GAIN (LOSS)
ON INVESTMENTS (NOTE 3)
Net realized gain on investments .................................      177              242             282
Change in net unrealized appreciation on investments .............     (440)            (840)           (842)
                                                                     ------           ------          ------

Net realized and unrealized
loss on investments ..............................................     (263)            (598)           (560)
                                                                     ------           ------          ------

Net Increase in Net Assets
Resulting from Operations ........................................  $   718           $1,200         $   956
                                                                     ======           ======          ======
</TABLE>

See Notes to Financial Statements


26   Statements of Operations                       American Century Investments

<TABLE>
<CAPTION>
                      STATEMENTS OF CHANGES IN NET ASSETS

Six Months Ended APRIL 30, 1997 (Unaudited) AND YEAR ENDED OCTOBER 31, 1996

                                             LIMITED-TERM          INTERMEDIATE-TERM             LONG-TERM
                                              TAX-EXEMPT              TAX-EXEMPT                TAX-EXEMPT

Increase (Decrease) in Net Assets         1997        1996         1997         1996        1997         1996
OPERATIONS                                                   ($ and Shares in Thousands)
<S>                                   <C>            <C>        <C>              <C>                     
Net investment income ............... $     981      $  2,306   $  1,798         $  3,787$  1,516$  3,007
Net realized gain on investments ....       177          23          242          185          282         27
Change in net unrealized
  appreciation (depreciation)
  on investments ....................      (440)       (100)        (840)        (538)        (842)       134
                                        -------     -------      -------      -------      -------    -------
Net increase in net assets
  resulting from operations .........       718       2,229        1,200        3,434          956      3,168
                                        -------     -------      -------      -------      -------    -------

DISTRIBUTIONS TO SHAREHOLDERS
From net investment income ..........      (981)     (2,306)      (1,798)      (3,787)      (1,516)    (3,007)
From net realized gains
  from investment transactions ......       (16)         --         (187)        (549)          --         --
                                        -------     -------      -------      -------      -------    -------
Decrease in net assets
  from distributions ................      (997)     (2,306)      (1,985)      (4,336)      (1,516)    (3,007)
                                        -------     -------      -------      -------      -------    -------

CAPITAL SHARE TRANSACTIONS
Proceeds from shares sold ...........    16,283      20,823        9,215       17,649       10,946     20,252
Proceeds from reinvestment
  of distributions ..................       901       2,061        1,697        3,711        1,309      2,575
Payments for shares redeemed ........   (21,176)    (31,778)     (18,533)     (20,138)     (16,201)   (20,213)
                                        -------     -------      -------      -------      -------    -------
Net increase (decrease)
  in net assets from
  capital share transactions ........    (3,992)     (8,894)      (7,621)       1,222       (3,946)     2,614
                                        -------     -------      -------      -------      -------    -------

Net increase (decrease)
  in net assets .....................    (4,271)     (8,971)      (8,406)         320       (4,506)     2,775

NET ASSETS
Beginning of period .................    49,866      58,837       80,568       80,248       60,772     57,997
                                        -------     -------      -------      -------      -------    -------

End of period .......................   $45,595     $49,866      $72,162      $80,568      $56,266    $60,772
                                        =======     =======      =======      =======      =======    =======

TRANSACTIONS IN SHARES OF THE FUNDS
Sold ................................     1,617       2,064          890        1,701        1,033      1,920
Issued in reinvestment
  of distributions ..................        90         204          164          359          123        245
Redeemed ............................    (2,104)     (3,148)      (1,793)      (1,949)      (1,532)    (1,925)
                                        -------     -------      -------      -------      -------    -------
Net increase (decrease) .............      (397)       (880)        (739)         111         (376)       240
                                        =======     =======      =======      =======      =======    =======
</TABLE>

See Notes to Financial Statements


Semiannual Report                       Statements of Changes in Net Assets   27


                         NOTES TO FINANCIAL STATEMENTS

APRIL 30, 1997 (UNAUDITED)

1. Organization and Summary of Significant Accounting Policies

Organization--American   Century  Mutual  Funds,   Inc.  (the   Corporation)  is
registered under the Investment  Company Act of 1940 as an open-end  diversified
management investment company. American Century - Benham Limited-Term Tax-Exempt
Fund (Limited-Term), American Century - Benham Intermediate-Term Tax-Exempt Fund
(Intermediate-Term),  and American  Century - Benham  Long-Term  Tax-Exempt Fund
(Long-Term) (the Funds) are three of the seventeen series of funds issued by the
Corporation.  The  investment  objective  of  Limited-Term  is  to  seek  income
generally  exempt from federal income taxes.  The Fund intends to pursue this by
investing in tax-exempt  bonds and  maintaining a weighted  average  maturity of
five years or less. The investment  objective of  Intermediate-Term is to seek a
competitive level of income generally exempt from federal income taxes. The Fund
intends to pursue  this by  investing  in  tax-exempt  bonds and  maintaining  a
weighted  average  maturity of three to ten years.  The investment  objective of
Long-Term is to seek a high level of income generally exempt from federal income
taxes.  The Fund  intends to pursue this by investing  in  tax-exempt  bonds and
maintaining a weighted average  maturity of ten years or greater.  The following
significant  accounting  policies,  related to all Funds, are in accordance with
accounting policies generally accepted in the investment company industry.

Security Valuations--Securities are valued through valuations obtained through a
commercial  pricing  service  or at the mean of the most  recent  bid and  asked
prices. When valuations are not readily available, securities are valued at fair
value as  determined  in  accordance  with  procedures  adopted  by the Board of
Directors.

Security  Transactions--Security  transactions  are  accounted  for on the  date
purchased  or  sold.  Net  realized  gains  and  losses  are  determined  on the
identified cost basis, which is also used for federal income tax purposes.

Investment Income--Interest income is recorded on the accrual basis and includes
amortization of discounts and premiums.

Repurchase  Agreements--The  Funds may enter  into  repurchase  agreements  with
institutions that the Funds'  investment  manager,  American Century  Investment
Management,  Inc. (ACIM),  has determined are creditworthy  pursuant to criteria
adopted by the Board of  Directors.  Each  repurchase  agreement  is recorded at
cost.  The  Funds  require  that  the  securities   purchased  in  a  repurchase
transaction be transferred to the custodian in a manner sufficient to enable the
Funds to obtain those  securities in the event of a default under the repurchase
agreement.  ACIM  monitors,  on a  daily  basis,  the  value  of the  securities
transferred  to ensure that the value,  including  interest,  of the  securities
under each repurchase  agreement is equal to or greater than amounts owed to the
Funds under each repurchase agreement.

Joint Trading  Account--Pursuant  to an Exemptive Order issued by the Securities
and  Exchange  Commission,  the Funds,  along with other  registered  investment
companies  having   management   agreements  with  ACIM  and  Benham  Management
Corporation, may transfer uninvested cash balances into a joint trading account.
These  balances  are  invested  in one or more  repurchase  agreements  that are
collateralized by U.S. Treasury or Agency obligations.

Income Tax Status--It is the Funds' policy to distribute all taxable income and
net capital gains to shareholders and to otherwise qualify as a regulated
investment company under provisions of the Internal Revenue Code. Accordingly,
no provision has been made for federal income taxes.

Distributions  to  Shareholders--Distributions  from net  investment  income are
declared daily and distributed  monthly.  Distributions  from net realized gains
are declared and paid annually.

The character of distributions  made during the year from net investment  income
or net  realized  gains may differ  from  their  ultimate  characterization  for
federal income tax purposes.  These differences are primarily due to differences
in the  recognition of income and expense items for financial  statement and tax
purposes.

Supplementary Information--Certain officers and directors of the Corporation are
also officers  and/or  directors,  and as a group,  controlling  stockholders of
American Century  Companies,  Inc., the parent of the  Corporation's  investment
manager,  ACIM,  the  Corporation's  distributor,  American  Century  Investment
Services,  Inc. and the Corporation's  transfer agent, American Century Services
Corporation.

Use of  Estimates--The  preparation of financial  statements in conformity  with
generally accepted  accounting  principles requires management to make estimates
and assumptions  that affect the reported  amounts of assets and liabilities and
disclosure of  contingent  assets and  liabilities  at the date of the financial
statements  and the reported  amounts of increases  and  decreases in net assets
from  operations  during the  period.  Actual  results  could  differ from these
estimates.


28   Notes to Financial Statements                  American Century Investments


                         NOTES TO FINANCIAL STATEMENTS

APRIL 30, 1997 (UNAUDITED)

- --------------------------------------------------------------------------------
2. Transactions with Related Parties

The Corporation  has entered into Management  Agreements with ACIM that provides
each Fund with  investment  advisory and  management  services in exchange for a
single,  unified fee.  The  Agreement  provides  that all expenses of the Funds,
except brokerage commissions,  taxes, interest,  expenses of those directors who
are not considered "interested persons" as defined in the Investment Company Act
of 1940 (including  counsel fees), and extraordinary  expenses,  will by paid by
ACIM.  The fee is computed  daily and paid monthly based on each Fund's  average
closing net assets  during the previous  month.  The annual  management  fee for
Limited-Term, Intermediate-Term, and Long-Term is 0.60%.

- --------------------------------------------------------------------------------
3. Investment Transactions

Investment  transactions  (excluding short-term  investments) for the six months
ended April 30, 1997, were as follows:

<TABLE>
                                                               LIMITED-TERM     INTERMEDIATE-TERM      LONG-TERM
                                                                                 ($ in Thousands)

PURCHASES
<S>                                                               <C>              <C>                <C>     
Municipal Debt Obligations ....................................   $20,695          $  7,669           $  9,086

PROCEEDS FROM SALES
Municipal Debt Obligations ....................................   $26,444           $15,202            $13,095

On April 30, 1997, the composition of unrealized appreciation  (depreciation) of
investment  securities  based on the aggregate cost of  investments  for federal
income tax purposes was as follows:

                                                               LIMITED-TERM     INTERMEDIATE-TERM      LONG-TERM
                                                                                 ($ in Thousands)

Appreciation ..................................................   $   114          $  1,337           $  2,196
(Depreciation) ................................................     (161)              (194)               (68)
Net ...........................................................      (47)             1,143              2,128
</TABLE>

The aggregate cost of  investments  for federal income tax purposes was the same
as the cost for financial reporting purposes.

- --------------------------------------------------------------------------------
4. Corporate Events

The following name changes became effective January 1, 1997:
<TABLE>

                    NEW NAMES                                                   FORMER NAMES
<S>                <C>                                                         <C>  
Funds' Issuer:      American Century Mutual Funds, Inc.                         Twentieth Century Investors, Inc.
Funds:              American Century - Benham Limited-Term Tax-Exempt Fund      Tax-Exempt Short-Term
                    American Century - Benham Intermediate-Term Tax-Exempt Fund Tax-Exempt Intermediate-Term
                    American Century - Benham Long-Term Tax-Exempt Fund         Tax-Exempt Long-Term
Distributor:        American Century Investment Services, Inc.                  Twentieth Century Securities, Inc.
Transfer Agent:     American Century Services Corporation                       Twentieth Century Services, Inc.
</TABLE>


Semiannual Report                             Notes to Financial Statements   30


<TABLE>
<CAPTION>
                              FINANCIAL HIGHLIGHTS
LIMITED-TERM TAX-EXEMPT

 For a Share Outstanding Throughout the Years Ended October 31 (except as noted)

                                                   1997(1)       1996         1995         1994         1993(2)
PER-SHARE DATA
<S>                                               <C>          <C>            <C>         <C>          <C>   
Net Asset Value,
Beginning of Period ............................  $10.08       $10.09         $9.95       $10.04       $10.00
Income From Investment Operations
  Net Investment Income ........................    0.20         0.43          0.44         0.36         0.21
  Net Realized and Unrealized Gain
  (Loss) on Investment Transactions ............   (0.06)       (0.01)         0.14        (0.09)        0.04
                                                  ------       ------        ------       ------       ------
  Total From
  Investment Operations ........................    0.14         0.42          0.58         0.27         0.25
                                                  ------       ------        ------       ------       ------
Distributions
  From Net Investment Income ...................   (0.20)       (0.43)        (0.44)       (0.36)       (0.21)
                                                  ------       ------        ------       ------       ------
Net Asset Value, End of Period .................  $10.02       $10.08        $10.09        $9.95       $10.04
                                                  ======       ======        ======        =====       ======
  Total Return(3) ..............................    1.45%        4.26%         5.95%        2.75%        2.55%

RATIOS/SUPPLEMENTAL DATA
Ratio of Operating Expenses
to Average Net Assets ..........................0.60%(4)     0.38%(5)         --(5)       --(5)         --(5)
Ratio of Net Investment Income
to Average Net Assets ..........................4.05%(4)         4.28%         4.38%       3.62%     3.09%(4)
Portfolio Turnover Rate ........................      42%          68%           78%         42%            3%
Net Assets, End
of Period (in thousands) .......................  $45,595     $49,866       $58,837     $60,857        $52,265

(1)  Six months ended April 30, 1997 (unaudited).

(2)  March 1, 1993 (inception) through October 31, 1993.

(3)  Total  return   assumes   reinvestment   of  dividends  and  capital  gains
     distributions, if any. Total returns for periods less than one year are not
     annualized.

(4)  Annualized.

(5)  The manager had voluntarily  waived its management fee through February 29,
     1996. In absence of the waiver,  the ratio of operating expenses to average
     net assets would have been 0.60%.
</TABLE>

See Notes to Financial Statements


30   Financial Highlights                           American Century Investments

<TABLE>
<CAPTION>
                              FINANCIAL HIGHLIGHTS
                          INTERMEDIATE-TERM TAX-EXEMPT

 For a Share Outstanding Throughout the Years Ended October 31 (except as noted)

                                      1997(1)       1996         1995         1994        1993(2)       1992(2)
PER-SHARE DATA
Net Asset Value,
<S>                                   <C>          <C>          <C>          <C>          <C>          <C>   
Beginning of Period ................. $10.35       $10.45       $10.01       $10.75       $10.27       $10.06
                                      ------       ------       ------       ------       ------       ------
Income From Investment Operations
  Net Investment Income .............   0.24         0.48         0.49         0.48         0.48         0.48
  Net Realized and Unrealized Gain (Loss)
  on Investment Transactions ........  (0.09)       (0.03)        0.52        (0.61)        0.55         0.21
                                      ------       ------       ------       ------       ------       ------
  Total From
  Investment Operations .............   0.15         0.45         1.01        (0.13)        1.03         0.69
                                      ------       ------       ------       ------       ------       ------
Distributions
  From Net Investment Income ........  (0.24)       (0.48)       (0.49)       (0.48)       (0.48)       (0.48)
  From Net Realized Gains
  on Investment Transactions ........  (0.02)       (0.07)       (0.08)       (0.13)       (0.07)       --
                                      ------       ------       ------       ------       ------       ------
  Total Distributions ...............  (0.26)       (0.55)       (0.57)       (0.61)       (0.55)       (0.48)
                                      ------       ------       ------       ------       ------       ------
Net Asset Value, End of Period ...... $10.24       $10.35       $10.45       $10.01       $10.75       $10.27
                                      ======       ======       ======       ======       ======       ======
  Total Return(3) ...................   1.50%        4.47%       10.41%       (1.25%)      10.25%        7.00%

Ratios/Supplemental Data
Ratio of Operating Expenses
to Average Net Assets ...............0.60%(4)        0.60%        0.60%        0.60%        0.72%     0.98%(5)
Ratio of Net Investment Income
to Average Net Assets ...............4.70%(4)        4.66%        4.77%        4.59%        4.51%        4.68%
Portfolio Turnover Rate. ............     10%          39%          32%          74%          38%          36%
Net Assets, End
of Period (in thousands) ............ $72,162     $80,568      $80,248      $81,400      $98,740       $76,745

(1)  Six months ended April 30, 1997 (unaudited).

(2)  The data  presented  has been  restated  to give effect to a 10 for 1 stock
     split in the form of a stock dividend that occurred on November 13, 1993.

(3)  Total  return   assumes   reinvestment   of  dividends  and  capital  gains
     distributions, if any. Total returns for periods less than one year are not
     annualized.

(4)  Annualized.

(5)  Expenses  are shown  net of  management  fees  waived  by the  manager  for
     low-balance account fees collected during the period.
</TABLE>


See Notes to Financial Statements


Semiannual Report                                      Financial Highlights   31

<TABLE>
<CAPTION>
                              FINANCIAL HIGHLIGHTS
                              LONG-TERM TAX-EXEMPT

                                 For a Share Outstanding Throughout the Years Ended October 31 (except as noted)

                                      1997(1)       1996         1995         1994        1993(2)       1992(2)

PER-SHARE DATA
Net Asset Value,
<S>                                   <C>          <C>           <C>         <C>          <C>          <C>   
Beginning of Period ................  $10.58       $10.54        $9.75       $11.10       $10.36       $10.23
                                      ------       ------       ------       ------       ------       ------
Income From Investment Operations
  Net Investment Income ............    0.27         0.53         0.53         0.52         0.53         0.53
  Net Realized and Unrealized Gain (Loss)
  on Investment Transactions .......   (0.10)        0.04         0.83        (1.01)        0.90         0.22
                                      ------       ------       ------       ------       ------       ------
  Total From
  Investment Operations ............    0.17         0.57         1.36        (0.49)        1.43         0.75
                                      ------       ------       ------       ------       ------       ------
Distributions
  From Net Investment Income .......   (0.27)       (0.53)       (0.53)       (0.52)       (0.53)       (0.53)
  From Net Realized Gains
  on Investment Transactions .......   --           --           (0.04)       (0.34)       (0.16)       (0.09)
  Total Distributions ..............   (0.27)       (0.53)       (0.57)       (0.86)       (0.69)       (0.62)
                                      ------       ------       ------       ------       ------       ------
Net Asset Value, End of Period .....  $10.48       $10.58       $10.54        $9.75       $11.10       $10.36
                                      ======       ======       ======        =====       ======       ======
  Total Return(3) ..................    1.63%        5.60%       14.45%       (4.70%)      14.32%        7.43%

Ratios/Supplemental Data
Ratio of Operating Expenses
to Average Net Assets .............. 0.60%(4)        0.59%        0.59%        0.60%        0.73%     0.98%(5)
Ratio of Net Investment Income
to Average Net Assets .............. 5.17%(4)        5.06%        5.24%        5.00%        4.90%        5.07%
Portfolio Turnover Rate ............      16%          60%          61%          66%          81%          88%
Net Assets, End
of Period (in thousands) ...........  $56,266      $60,772      $57,997      $50,964      $70,757      $61,825

(1)  Six months ended April 30, 1997 (unaudited).

(2)  The data  presented  has been  restated  to give effect to a 10 for 1 stock
     split in the form of a stock dividend that occurred on November 13, 1993.

(3)  Total  return   assumes   reinvestment   of  dividends  and  capital  gains
     distributions, if any. Total returns for periods less than one year are not
     annualized.

(4)  Annualized.

(5)  Expenses  are shown  net of  management  fees  waived  by the  manager  for
     low-balance account fees collected during the period.
</TABLE>

See Notes to Financial Statements


32   Financial Highlights                           American Century Investments


                                     NOTES

Semiannual Report                                                     Notes   33


                                     NOTES

34   Notes                                          American Century Investments


                                     NOTES

Semiannual Report                                                     Notes   35


                             BACKGROUND INFORMATION

Investment Philosophy & Policies

The Benham Group offers 42 fixed-income  funds,  ranging from money market funds
to long-term bond funds and including both taxable and tax-exempt funds.

Limited-Term  Tax-Exempt  is a  variable-price  bond fund that  seeks to provide
interest  income  exempt from  federal  income  taxes by  investing in municipal
securities.  The fund must  maintain a weighted  average  maturity of 5 years or
less.

Intermediate-Term Tax-Exempt is a variable-price bond fund that seeks to provide
interest  income  exempt from  federal  income  taxes by  investing in municipal
securities. The fund must maintain a weighted average maturity of 3-10 years.

Long-Term  Tax-Exempt  is a  variable-price  bond  fund  that  seeks to  provide
interest  income  exempt from  federal  income  taxes by  investing in municipal
securities.  The fund must maintain a weighted  average maturity of greater than
10 years.

An  investment  in the  funds is  neither  insured  nor  guaranteed  by the U.S.
government.  There is no assurance that the funds will achieve their  respective
investment objectives.

Comparative Indices

The indices listed below are used in the report to serve as a comparison for the
performance of a fund. They are not investment products available for purchase.

The Merrill  Lynch 0- to 3-Year  Municipal  Index is  composed  of 23  municipal
securities with an average maturity of approximately two years. The bonds in the
index have an average rating of AA1.

The Lehman Brothers,  Inc.  Five-Year  Municipal  General  Obligation Index is a
municipal bond index composed of more than 11,000 bonds with  maturities of four
to six years.  The bonds are rated BBB or higher by  Standard & Poor's,  with an
average rating of AA. The average maturity of the index is five years.

The Lehman Brothers,  Inc.  Long-Term  Municipal Bond Index is composed of 8,000
municipal  bonds.  The bonds  are all  investment-grade,  fixed-rate,  long-term
maturities (greater than two years) and are selected from issues larger than $50
million dated since January 1994.

Lipper Rankings

Lipper Analytical  Services,  Inc. is an independent mutual fund ranking service
that groups funds according to their investment  objectives.  Rankings are based
on average  annual  returns  for each fund in a given  category  for the periods
indicated. Rankings are not included for periods less than one year.

The Lipper categories for the Tax-Exempt funds are:

Short  Municipal  Debt Funds  (Limited-Term  Tax-Exempt)--funds  that  invest in
municipal  debt issues with  dollar-weighted  average  maturities of less than 3
years.

Intermediate  Municipal Debt Funds  (Intermediate-Term  Tax-Exempt)--funds  that
invest in municipal debt issues with dollar-weighted  average maturities of 5 to
10 years.

General Municipal Debt Funds (Long-Term  Tax-Exempt)--funds that invest at least
65% of their  assets in  municipal  debt issues in the top four  credit  ratings
(AAA, AA, A and BBB).

PORTFOLIO MANAGEMENT TEAM
Senior Municipal Portfolio Manager      Dave MacEwen
Municipal Portfolio Manager             Joel Silva
Municipal Credit Research Manager       Steven Permut
Credit Analysts                         Scott Lord, Bill McClintock,
                                        David Moore, Tim Benham


36   Background Information                         American Century Investments


                                    GLOSSARY

Returns

o Total  Return  figures  show the overall  percentage  change in the value of a
hypothetical  investment  in  the  fund  and  assume  that  all  of  the  fund's
distributions are reinvested.

o Average Annual Returns  illustrate the annually  compounded returns that would
have produced the fund's cumulative total returns if the fund's  performance had
been  constant  over the  entire  period.  Average  annual  returns  smooth  out
variations  in a fund's  return;  they are not the same as  fiscal  year-by-year
results.  For  fiscal  year-by-year  returns,  please  refer  to the  "Financial
Highlights" on pages 30-32. 

Yields

o 30-Day SEC Yield  represents net  investment  income earned by the fund over a
30-day period,  expressed as an annualized  percentage  rate based on the fund's
share price at the end of the 30-day period. The SEC yield should be regarded as
an estimate  of the fund's  investment  income,  and it may not equal the fund's
actual income distribution rate, the income paid to a shareholder's  account, or
the income reported in the fund's financial statements.

o  Tax-Equivalent  Yields show the taxable  yields that  investors  in a federal
income tax bracket would have to earn before taxes to equal the fund's  tax-free
yield.

Bond Portfolio Structures

o Barbell  Structure--a  structure  that  overweights  a portfolio in short- and
long-term  securities  and  underweights   intermediate-term   securities.  This
structure  tends to perform  best when the yield  curve is moving  from steep to
flat.  (Short-term  rates are rising faster than long-term  rates,  or long-term
rates are falling faster than short-term rates.)

o Bullet  Structure--a  structure  that clusters a portfolio's  bond  maturities
around a single maturity (usually an intermediate-term maturity). This structure
tends  to  perform  best  when the  yield  curve is  moving  from  flat to steep
(long-term  rates are rising faster than short-term  rates, or short-term  rates
are falling faster than long-term rates).

o Ladder  Structure--a  balanced structure that staggers bond maturities so they
occur at regular  intervals.  This structure tends to perform best when interest
rates are  relatively  stable,  and it  provides a regular  schedule of maturing
securities.

Investment Terms

o Basis Point--a basis point equals one  one-hundredth of a percentage point (or
0.01%). Therefore, 100 basis points equals one percentage point (or 1%).

o Yield Curve--a graphic representation of the relationship between maturity and
yield  for  fixed-income   securities.   Yield  curve  graphs  plot  lengthening
maturities along the horizontal axis and rising yields along the vertical axis.

Statistical Terminology

o Number of Securities--the  number of different  securities issuances held by a
fund on a given date.

o  Weighted  Average  Maturity--measures  the  average  amount of time until the
securities in a bond portfolio mature, weighted by dollar amount.

o Average  Duration--measures the interest rate sensitivity of a bond portfolio.
Measured in years, average duration represents the approximate percentage change
in the  value  of a bond  portfolio  if  interest  rates  move up or down by one
percentage point.

o Expense Ratio--the  operating expenses of the fund,  expressed as a percentage
of average net assets.  Shareholders pay an annual fee to the investment manager
for  investment  advisory  and  management  services.  The expenses and fees are
deducted from fund income, not from each shareholder's account.

Types of Municipal Securities

o  COPs/Leases--securities  issued to finance public property improvements (such
as city halls and police  stations) and  equipment  purchases.  Certificates  of
participation  represent long-term debt obligations,  while leases have a higher
risk profile than GOs because they require annual appropriation.

o GO  Bonds--general  obligation  securities  backed by the taxing  power of the
issuer.

o  Land-Secured  Bonds--securities  such as Mello-Roos  bonds and 1915-Act bonds
that are issued to finance real estate development projects.

o Prerefunded Bonds/ETM Bonds--securities  refinanced or escrowed to maturity by
the issuer because of their premium coupons (higher-than-market interest rates).
These  bonds  tend to have  higher  credit  ratings  because  they are backed by
Treasury securities.

o  Revenue  Bonds--securities  backed by  revenues  from  sales  taxes or from a
specific  project,  system or facility (such as a hospital,  electric utility or
water system).


Semiannual Report                                                  Glossary   37


[american century logo]
American
Century(sm)

P.O. Box 419200
Kansas City, Missouri
64141-6200

Investor Services:
1-800-345-2021 or 816-531-5575

Automated Information Line:
1-800-345-8765

Telecommunications Device for the Deaf:
1-800-634-4113 or 816-444-3485

Fax: 816-340-7962

Internet: www.americancentury.com


AMERICAN CENTURY MUTUAL FUNDS, INC.

Investment Manager
AMERICAN CENTURY INVESTMENT MANAGEMENT

This  report and the  statements  it  contains  are  submitted  for the  general
information of our  shareholders.  The report is not authorized for distribution
to  prospective  investors  unless  preceded  or  accompanied  by  an  effective
prospectus.

American Century Investment Services, Inc.


9706           [recycled logo]
SH-BKT-8699       Recycled
<PAGE>
                               SEMIANNUAL REPORT

                            [american century logo]
                                    American
                                  Century(sm)

                                 April 30, 1997

                                     BENHAM
                                     GROUP

                             Short-Term Government
                          Intermediate-Term Government

[front cover]

                               TABLE OF CONTENTS

Report Highlights........................................... 1
Our Message to You.......................................... 2
Period Overview............................................. 3
Short-Term Government
Performance & Portfolio Information......................... 4
Management Q & A............................................ 5
Schedule of Investments..................................... 8
Financial Highlights........................................19
Intermediate-Term Government
Performance & Portfolio Information......................... 9
Management Q & A............................................10
Schedule of Investments.....................................13
Financial Highlights........................................20
Statements of Assets and Liabilities........................14
Statements of Operations....................................15
Statements of Changes in Net Assets.........................16
Notes to Financial Statements...............................17
Retirement Account Information..............................21
Background Information
Investment Philosophy & Policies............................24
Comparative Indices.........................................24
Lipper Rankings.............................................24
Portfolio Management Team...................................24
Glossary....................................................25

American Century  Investments offers you nearly 70 fund choices covering stocks,
bonds, money markets,  specialty investments and blended portfolios. To help you
find the funds that may meet your needs, we have divided  American Century funds
into three groups based on investment style and objectives.  These groups, which
appear below, are designed to help simplify your fund decisions.

                  American Century Investments--Family of Funds

     BENHAM GROUP           AMERICAN CENTURY GROUP       TWENTIETH CENTURY GROUP

  MONEY MARKET FUNDS          ASSET ALLOCATION &
 GOVERNMENT BOND FUNDS          BALANCED FUNDS              U.S. GROWTH FUNDS
DIVERSIFIED BOND FUNDS    CONSERVATIVE EQUITY FUNDS        INTERNATIONAL FUNDS
 MUNICIPAL BOND FUNDS          SPECIALTY FUNDS

 Short-Term Government
  Intermediate-Term
      Government


We welcome your comments or questions about this report.  
See the back cover for ways to contact us by mail, phone or e-mail.

Twentieth  Century and the Benham Group are registered marks of American Century
Services Corporation and Benham Management Corporation,  respectively.  American
Century is a service mark of American Century Services Corporation.


                                                    American Century Investments


                               REPORT HIGHLIGHTS

Period Overview

o    U.S.  economic  growth  accelerated  during the six months  ended April 30,
     1997, while inflation remained relatively subdued.

o    The Federal Reserve raised  short-term  interest rates in March to head off
     potential inflation and slow the rapid pace of economic growth.

o    U.S.  government  securities  produced  modest returns during the six-month
     period.

o    Overall,  bond prices fell as yields rose, but interest income enabled most
     government bonds to produce positive returns.

o    Mortgage-backed  securities were the best-performing government securities,
     followed by government agency and Treasury securities.


Short-Term Government

o    The  fund's   performance  kept  pace  with  the  average  short-term  U.S.
     government fund during the six months ended April 30, 1997.

o    The fund was positioned  defensively for most of the period to mitigate the
     negative effects of rising interest rates.

o    The fund increased its holdings of  mortgage-backed  securities  because of
     their attractive return potential.

o    The fund also added more callable government agency securities,  which have
     performance characteristics that are similar to mortgage-backed securities.

o    Going forward,  we plan to remain defensive because of our expectations for
     higher short-term interest rates in the coming months.


Intermediate-Term Government

o    The fund's  performance kept pace with the average  intermediate-term  U.S.
     government fund during the six months ended April 30, 1997.

o    The fund was positioned  defensively for most of the period to mitigate the
     negative effects of rising interest rates.

o    The fund  maintained  an asset mix of  approximately  75% Treasurys and 25%
     mortgage-backed securities throughout the period.

o    Because  of  liquidity  problems  related  to the  fund's  small  size,  we
     continued to avoid government agency securities.

o    Going forward,  we plan to remain defensive because of our expectations for
     higher short-term interest rates in the coming months.


                                   Short-Term
                    Total Returns:             AS OF 4/30/97
                      6 Months                        1.98%*
                      1 Year                           5.49%
                    Net Assets:               $326.7 million
                      (AS of 4/30/97)
                    Inception Date:                 12/15/82
                    Ticker Symbol:                     TWUSX

                               Intermediate-Term
                    Total Returns:             AS OF 4/30/97
                      6 Months                        1.35%*
                      1 Year                           5.80%
                    Net Assets:                $24.9 million
                      (AS of 4/30/97)
                    Inception Date:                   3/1/94
                    Ticker Symbol:                     TWGIX

                    * Not annualized.

                 Many of the investment terms in this report are
                       defined in the Glossary on page 25.


Semiannual Report                                         Report Highlights    1


                               OUR MESSAGE TO YOU

April 30,  1997,  marked the end of an eventful  period for our company and U.S.
bond markets.  U.S. government  securities posted modest returns as accelerating
first-quarter  economic growth sent bond yields higher.  In the following pages,
our investment management team provides further details about the market and how
your fund was managed during the period.

In January,  nearly two years of integration  between  Twentieth Century and The
Benham  Group   culminated  when  we  began  serving  you  as  American  Century
Investments.  Under this new name we have  combined  our  offerings of nearly 70
funds.

The new name also introduces three new groupings for the funds--the Benham Group
(money market and bond funds),  the American  Century  Group (asset  allocation,
balanced,  conservative  equity and specialty  funds) and the Twentieth  Century
Group  (aggressive  growth  and  international  equity  funds).  The  Short- and
Intermediate-Term  Government  funds have joined the Benham Group  because their
investment goals match key attributes of that group.

By now,  you should have  received a proxy  statement  and ballot that  proposes
several  changes to your fund. In order to  streamline  and simplify our list of
fund   offerings,   we  are  proposing  to  merge  several  funds  with  similar
characteristics  and  investment   objectives.   The  proxy  statement  includes
proposals to merge the Short-Term  Government fund into the existing  Adjustable
Rate Government Securities fund and the  Intermediate-Term  Government fund into
the existing  Intermediate-Term Treasury fund. The proxy statement contains more
details  about  the  proposed  changes;  we  strongly  encourage  you to read it
carefully and take part in the proxy vote if you have not already done so.

In  reviewing  this report,  you may notice some  changes.  Based on  investors'
feedback,  our  shareholder  reports have been  redesigned  with added features,
including a report  summary,  a glossary,  more charts and graphs,  and expanded
management Q & A and background information sections.

These are  examples  of how we  continue  working  to  provide  information  and
services  that are useful and  convenient  to  investors  in our funds.  We look
forward to sharing other helpful changes with you.


Sincerely,

/s/James E. Stowers III                     /s/James M. Benham
James E. Stowers III                        James M. Benham
President and Chief Executive Officer       Vice Chairman
American Century Companies                  American Century Companies


2    Our Message to You                             American Century Investments


                                PERIOD OVERVIEW

U.S. Economy

U.S.  economic  growth  accelerated  during the six months ended April 30, 1997.
After moderating throughout the summer of 1996, economic growth rebounded in the
fourth quarter as strong employment  growth,  increased  consumer spending and a
robust housing market fueled an annualized growth rate of 3.8%. The U.S. economy
continued to pick up speed in the first quarter of 1997, surging ahead at a 5.8%
annual rate.

Although  such  a  strong  level  of  economic  growth  has  historically   been
accompanied by rising prices,  inflation  remained under  control--the  consumer
price  index rose at an annual  rate of 3.2% during the  six-month  period.  But
recent  evidence of  increasing  wage  pressures--which  are often  passed on to
consumers  in the form of  higher  prices--led  the  Federal  Reserve  to make a
pre-emptive  strike against  inflation by raising  short-term  interest rates in
March. The Fed raised its federal funds rate target (the overnight  lending rate
targeted  by the Fed for large  loans  between  commercial  banks) from 5.25% to
5.50%.

U.S. Government Bonds

U.S.  government  securities produced modest returns during the six months ended
April 30. Rising  yields (see the graph above)  caused bond prices to fall,  but
the  interest  income  paid out to  bondholders  offset  nearly all of the price
declines.  Short-term  securities,  which usually suffer less price depreciation
than  longer-term  securities when interest rates rise, were the best performers
during the period. For example, the two-year Treasury note posted a 2.38% return
for the six-month period, while the 30-year Treasury bond returned -0.47%.

Bond yields fell (and bond prices rose) at the beginning of the six-month period
in response to evidence of moderating  U.S.  economic  growth and low inflation.
But by the beginning of 1997, stronger economic growth and rising wage pressures
rekindled concerns about inflation.  As a result,  bond yields soared throughout
the first quarter of 1997. The 30-year Treasury bond yield, which fell as low as
6.35% in December, climbed to 7.10% by the end of March. The bond market settled
down a little in April, rallying slightly as inflation remained subdued.

Mortgage-backed securities were the top performers among government bonds during
the six-month  period,  followed by government  agency and Treasury  securities.
With bond prices  declining  slightly  overall,  yield was the most  significant
contributor to bond returns. Mortgage-backed securities tend to have the highest
yields among government  securities,  while Treasury securities tend to have the
lowest yields.  Over the past two years,  mortgage-backed  and government agency
securities have outperformed Treasurys; as a result, the gap--or spread--between
the yields of  mortgage-backed,  agency and  Treasury  securities  has  narrowed
significantly.

[line graph - data below]

TREASURY YIELD CURVES

Years to Maturity       4/30/97         10/31/96
1                       5.88             5.404
2                       6.27             5.732
3                       6.39             5.86
4                       6.47             5.89
5                       6.56             6.07
6                       6.6              6.105
7                       6.64             6.14
8                       6.66             6.207
9                       6.68             6.274
10                      6.7              6.341
11                      6.733            6.3758
12                      6.766            6.4106
13                      6.799            6.4454
14                      6.832            6.4802
15                      6.865            6.515
16                      6.898            6.55
17                      6.931            6.585
18                      6.964            6.62
19                      6.997            6.655
20                      7.03             6.69
21                      7.022            6.685
22                      7.014            6.68
23                      7.006            6.675
24                      6.998            6.67
25                      6.99             6.665
26                      6.982            6.6602
27                      6.974            6.6554
28                      6.966            6.6506
29                      6.958            6.6458
30                      6.95             6.641
Source: Bloomberg Financial Markets


Semiannual Report                                           Period Overview    3


<TABLE>
<CAPTION>
                             SHORT-TERM GOVERNMENT

                                                                        AVERAGE ANNUAL RETURNS
                                            6 MONTHS       1 YEAR        3 YEARS       5 YEARS       10 YEARS
TOTAL RETURNS AS OF APRIL 30, 1997
<S>                                           <C>           <C>           <C>           <C>            <C>  
Short-Term Government                         1.98%         5.49%         5.56%         4.73%          6.24%
Merrill Lynch 1- to 3-Year Government Index   2.26%         6.09%         6.25%         5.68%          7.28%
Average Short U.S. Government Fund(1)         2.06%         5.57%         5.40%         4.93%          6.39%
Fund's Ranking Among
Short U.S. Government Funds(1)                 --       36 out of 58  21 out of 46  11 out of 17    6 out of 8

(1)  According to Lipper Analytical Services.
</TABLE>

See pages 24-25 for more information  about returns,  the comparative  index and
Lipper fund rankings.

[mountain graph - data below]

GROWTH OF $10,000 OVER TEN YEARS
Value on 4/30/97

Short-Term Government      $18,311
Merrill Lynch 1- to 3-Year Govt. Index      $20,202

            Short-Term Government      Merrill Lynch 1- to 3-Year Govt. Index
Apr-87            $10,000                             $10,000
Jun-87            $10,092                             $10,133
Sep-87            $10,022                             $10,151
Dec-87            $10,410                             $10,504
Mar-88            $10,686                             $10,781
Jun-88            $10,784                             $10,893
Sep-88            $10,934                             $11,052
Dec-88            $10,997                             $11,158
Mar-89            $11,106                             $11,297
Jun-89            $11,675                             $11,859
Sep-89            $11,785                             $12,031
Dec-89            $12,096                             $12,371
Mar-90            $12,057                             $12,481
Jun-90            $12,350                             $12,831
Sep-90            $12,581                             $13,137
Dec-90            $13,008                             $13,574
Mar-91            $13,222                             $13,873
Jun-91            $13,449                             $14,146
Sep-91            $13,953                             $14,621
Dec-91            $14,522                             $15,160
Mar-92            $14,400                             $15,183
Jun-92            $14,793                             $15,620
Sep-92            $15,222                             $16,085
Dec-92            $15,160                             $16,115
Mar-93            $15,448                             $16,471
Jun-93            $15,579                             $16,648
Sep-93            $15,743                             $16,887
Dec-93            $15,793                             $16,987
Mar-94            $15,631                             $16,902
Jun-94            $15,591                             $16,916
Sep-94            $15,722                             $17,083
Dec-94            $15,715                             $17,083
Mar-95            $16,214                             $17,657
Jun-95            $16,707                             $18,223
Sep-95            $16,938                             $18,496
Dec-95            $17,366                             $18,962
Mar-96            $17,358                             $19,025
Jun-96            $17,519                             $19,217
Sep-96            $17,763                             $19,535
Dec-96            $18,081                             $19,906
Mar-97            $18,171                             $20,038
Apr-97            $18,311                             $20,202

Past  performance  does not  guarantee  future  results.  Investment  return and
principal  value will fluctuate,  and redemption  value may be more or less than
original cost.

The line representing the fund's total return includes  operating expenses (such
as transaction  costs and management fees) that reduce returns,  while the total
return line of the index does not.

PORTFOLIO AT A GLANCE
                            4/30/97   10/31/96
Number of Securities          26         27
Weighted Average Maturity  1.8 years  2.0 years
Average Duration           1.6 years  1.7 years
Expense Ratio               0.70%*      0.70%

* Annualized.

YIELD AS OF APRIL 30, 1997
                                       30-DAY
                                         SEC
                                        Yield
Short-Term Government                   5.71%

Yield is defined in the Glossary on page 25.


4    Short-Term Government                          American Century Investments


                             SHORT-TERM GOVERNMENT

Management Q & A

An  interview  with  Bob  Gahagan,  a senior  portfolio  manager  on the  Benham
Government funds management team.

How did the fund perform?

The fund kept pace with its peer group  average.  For the six months ended April
30,  1997,  the fund  posted a total  return of 1.98%,  compared  with the 2.06%
average  return  of the 62  "Short  U.S.  Government  Funds"  tracked  by Lipper
Analytical Services. (See the Total Returns table on the previous page for other
fund performance comparisons.)

How was the fund positioned during the period?

For the most part, the fund was positioned defensively over the past six months.
Stronger  economic growth in late 1996 and early 1997 prompted concern about the
possibility of a Federal Reserve interest rate increase.  To reduce the negative
impact of higher  rates on the fund's  share  price,  we  maintained  a cautious
average maturity and duration.

We also continued to cut the fund's Treasury  holdings while expanding its stake
in government agency and mortgage-backed  securities. This strategy was designed
to maintain the fund's yield despite a shorter average maturity and duration.

[bar graph - data below]

SHORT-TERM  GOVERNMENT'S  ONE-YEAR RETURNS FOR THE PAST TEN YEARS (Periods ended
April 30)

          Short-Term Government   Merrill Lynch 1- to 3-Year Govt. Index
4/30/88           6.81%                            7.69%
4/30/89           5.46%                            6.23%
4/30/90           6.87%                            9.03%
4/30/91          10.80%                           11.98%
4/30/92           8.93%                            9.41%
4/30/93           6.98%                            8.16%
4/30/94           0.15%                            1.63%
4/30/95           4.97%                            5.77%
4/30/96           6.22%                            6.89%
4/30/97           5.49%                            6.09%

This graph  illustrates  the fund's  returns over the past 10 years and compares
them with the  index's  returns.  The fund's  total  returns  include  operating
expenses, while the index's do not. See page 24 for a definition of the index.


Semiannual Report                                     Short-Term Government    5


                             SHORT-TERM GOVERNMENT

Mortgage-backed securities now make up 40% of the fund's portfolio,  compared to
30% six months ago. Why the significant increase?

We felt that  mortgage-backed  securities  offered  the highest  expected  total
return based on the prevailing  market  conditions.  Mortgage-backed  securities
tend to produce better returns than other  government  securities  when interest
rates are  relatively  stable because they are the  highest-yielding  government
securities.  Even a period of moderate interest rate volatility can be favorable
for  mortgage-backed  securities,  as long as there  are no  sharp  or  extended
interest rate shifts.

As it turned  out,  mortgage-backed  securities  outperformed  other  government
securities by a wide margin during the six-month period.  Interest rates shifted
gradually  throughout the period and only rose slightly overall.  Another factor
favoring    mortgage-backed    securities    was   demand    from    "crossover"
buyers--investors who typically purchase other types of fixed-income  securities
but who were drawn by the attractive total return  potential of  mortgage-backed
securities.

What about the fund's government agency securities?

We held about the same percentage of agency  securities in the fund's  portfolio
throughout the period,  but we adjusted the composition a little. We sold nearly
all of the fund's non-callable  agency securities,  replacing them with callable
agency securities.  This emphasis on callable  securities made the fund's agency
holdings behave more like mortgage-backed securities.

How so?

Callable  agency  securities  have a "call"  option,  which gives the issuer the
opportunity to pay off the securities at a prearranged date before maturity.  In
the same way that homeowners refinance their mortgages when interest rates fall,
government  agencies  will  usually  exercise a call option  when rates  decline
because they can issue new,  lower-yielding  securities  to replace the existing
callable  securities.  As a result,  callable agency  securities tend to perform
better when interest rates are  relatively  stable or slightly  rising.  This is
similar to the ideal environment for mortgage-backed securities.

[pie charts]

PORTFOLIO COMPOSITION BY SECURITY TYPE (as of 4/30/97)
Mortgage-Backed
Securities 40%
U.S. Treasury Securities 31%
U.S. Government Agency
Securities 23%
Cash 6%

PORTFOLIO COMPOSITION BY SECURITY TYPE (as of 10/31/96)
U.S. Treasury Securities 44%
Mortgage-Backed
Securities 30%
U.S. Government Agency
Securities 26%


6    Short-Term Government                          American Century Investments


                             SHORT-TERM GOVERNMENT

Do you plan to maintain this  concentration in callable agency  securities going
forward?

Yes,  although we'll be very selective.  Based on our interest rate outlook,  we
think certain  callable  agency  securities  offer higher expected total returns
than either Treasury or non-callable agency securities.  In general,  government
agency  securities  tend to provide higher yields than  Treasurys,  but callable
agency securities  typically yield more than  non-callable  agency securities to
compensate  for the risk  that the  issuer  will pay off the  callable  security
early.

The yield differential--or spread--between short-term Treasurys and non-callable
agency  securities  is  extremely   narrow,   which  limits  the  potential  for
non-callables  to  outperform  Treasurys.  On the other hand,  the yield  spread
between  Treasurys and selected  callable agency securities is still wide enough
for callables to outperform, given our interest rate outlook.

And what is your interest rate outlook for the next six months?

Continued strength in the economy will likely lead to higher short-term interest
rates. The U.S. economy picked up steam in the first quarter of 1997, growing at
a 5.8% annual rate. Although that level of growth is probably unsustainable,  we
feel that the pieces  are in place for  continued  healthy  economic  growth.  A
28-year high in consumer  confidence,  the lowest  unemployment rate since 1973,
and solid income growth suggest the possibility of increased  consumer  spending
in the months ahead.

We expect  these  economic  conditions  to put  further  pressure on the Federal
Reserve to continue  raising  short-term  interest rates in order to slow growth
and restrict inflationary pressures.  One key factor that we will be watching is
the labor market.  With  unemployment at its lowest level in more than 23 years,
we believe the risks are clearly on the upside for higher  wages.  Rising  labor
costs,  which often  translate  into higher prices for  consumers,  would likely
trigger additional Fed rate hikes.

With this  outlook  in mind,  what are your plans for the fund over the next six
months?

Since we  expect  short-term  rates  to rise,  we plan to  maintain  the  fund's
defensive  positioning in the coming months. This approach should help limit any
price  depreciation  resulting  from rising  yields.  However,  we will  closely
monitor economic and inflationary conditions,  and we'll make adjustments if the
environment changes.

We also plan to  maintain  the  fund's  current  asset  allocation,  with  about
two-thirds of the fund's assets devoted to mortgage-backed and government agency
securities. At some point in the coming months, we may look to reduce the fund's
agency  holdings  if  yield  spreads  between  short-term  Treasury  and  agency
securities continue to narrow.

In July,  fund  shareholders  will vote on a proposal to merge the fund with the
Benham  Adjustable Rate Government  Securities fund. If this merger is approved,
how will it affect the fund's management?

Shareholders  will see  virtually  no change to the fund's  management.  The new
combined fund will retain nearly all of this fund's  investment  objectives  and
policies.  The only significant  difference is that the new fund will have lower
management fees and expenses.

(PLEASE REVIEW THE PROXY STATEMENT FOR INFORMATION ABOUT THE MERGER,  AND PLEASE
REMEMBER TO VOTE YOUR PROXY.)


Semiannual Report                                     Short-Term Government    7


                            SCHEDULE OF INVESTMENTS
                             SHORT-TERM GOVERNMENT

APRIL 30, 1997 (UNAUDITED)

Principal Amount                ($ in Thousands)                        Value
- --------------------------------------------------------------------------------

U.S. TREASURY SECURITIES
$    17,580   U.S. Treasury Notes, 7.25%,
                2/15/98                                           $  17,761
     15,600   U.S. Treasury Notes, 6.125%,
                3/31/98                                              15,634
     19,490   U.S. Treasury Notes, 5.875%,
                4/30/98                                              19,472
     19,000   U.S. Treasury Notes, 5.875%,
                8/15/98                                              18,947
     12,000   U.S. Treasury Notes, 5.875%,
                10/31/98                                             11,947
      1,600   U.S. Treasury Notes, 5.00%,
                2/15/99                                               1,567
     15,000   U.S. Treasury Notes, 5.875%,
                3/31/99                                              14,902
                                                                   --------
TOTAL U.S. TREASURY SECURITIES--30.8%                              $100,230
   (Cost $100,159)                                                 --------

U.S. GOVERNMENT AGENCY SECURITIES
     12,367   FHLB, 6.21%, 3/29/99                                   12,324
     14,000   FHLB, 6.685%, 11/5/99                                  14,003
     18,000   FHLB, 6.605%, 11/12/99                                 17,989
     20,000   FNMA, 7.00%, 8/11/99                                   20,063
     10,000   FNMA, 6.76%, 11/14/01                                   9,905
                                                                   --------
TOTAL U.S. GOVERNMENT AGENCY
SECURITIES--22.9%                                                    74,284
   (Cost $89,051)                                                  --------

MORTGAGE-BACKED SECURITIES(1)
     12,562   FHLMC REMIC, Series 1344,
                Class B TAC, 6.00%, 10/15/05                         12,477
     13,714   FHLMC REMIC, Series 1861,
                Class E SEQ, 6.50%, 8/15/20                          13,490
     10,973   FHLMC REMIC, Series 1558,
                Class A TAC, 6.00%, 5/15/22                          10,778
     14,992   FNMA REMIC, Series 1996-53,
                Class A SEQ, 6.50%, 12/25/03                         14,982
      8,298   FNMA REMIC, Series 1993-93,
                Class C PAC, 5.50%, 2/25/06                           8,187

Principal Amount                ($ in Thousands)                        Value
- --------------------------------------------------------------------------------

$    13,210   FNMA REMIC, Series 1997-31,
                Class B SEQ, 6.00%, 4/18/07                      $   12,815
      2,148   FNMA REMIC, Series 1993-185,
                Class PB PAC, 4.90%, 4/25/09                          2,142
     21,700   FNMA REMIC, Series 1993-187,
                Class D PAC, 5.50%, 12/25/12                         21,503
      8,285   FNMA REMIC, Series 1996-10,
                Class A SEQ, 6.50%, 11/25/17                          8,205
      9,265   FNMA REMIC, Series 1996-12,
                Class A SEQ, 6.50%, 12/25/17                          9,163
      6,649   FNMA REMIC, Series G93-29,
                Class A SEQ, 6.65%, 10/25/18                          6,585
     11,169   FNMA REMIC, Series 1995-22,
                Class A, 7.00%, 8/25/23                              11,108
                                                                   --------
TOTAL MORTGAGE-BACKED
SECURITIES--40.4%                                                   131,435
   (Cost $131,159)                                                 --------

TEMPORARY CASH INVESTMENTS
$15,000 par value FHLB Discount Note,
   5.36%, 5/6/97(2)                                                  14,989
                                                                   --------
Repurchase Agreement, J.P. Morgan Securities,
   Inc., (U.S. Treasury obligations), in a
   joint trading account at 5.375%,
   dated 4/30/97, due 5/1/97
   (Delivery value $4,196)                                            4,195
                                                                   --------
TOTAL TEMPORARY CASH INVESTMENTS--5.9%                               19,184
   (Cost $4,195)                                                   --------

TOTAL INVESTMENT SECURITIES--100.0%                                $325,133
   (Cost $324,564)                                                 ========

Notes to Schedule of Investments
FHLB = Federal Home Loan Bank
FHLMC = Federal Home Loan Mortgage Corporation
FNMA = Federal National Mortgage Association
(1)  Final maturity indicated.  Expected remaining maturity used for purposes of
     calculating the weighted average portfolio maturity.
(2)  Rate disclosed represents effective yield to maturity as of April 30, 1997.

See Notes to Financial Statements


8    Short-Term Government                          American Century Investments


<TABLE>
<CAPTION>
                          INTERMEDIATE-TERM GOVERNMENT

                                                                                AVERAGE ANNUAL RETURNS
                                                          6 MONTHS       1 YEAR         3 YEARS    LIFE OF FUND
TOTAL RETURNS AS OF APRIL 30, 1997
<S>                                                         <C>          <C>           <C>           <C>  
Intermediate-Term Government                                1.35%         5.80%          5.77%         4.96%
Lehman Intermediate Government Bond Index                   1.77%         6.24%          6.64%         5.57%
Average Intermediate U.S. Government Fund(1)                1.34%         5.85%          6.05%         5.57%(2)
Fund's Ranking Among
Intermediate U.S. Government Funds(1)                        --       62 out of 122  56 out of 83 47 out of 81(2)
</TABLE>

(1)  According to Lipper Analytical Services.
(2)  Since  3/31/94,  the date nearest the fund's  inception  for which data are
     available.  Inception date was March 1, 1994.

See pages 24-25 for more information  about returns,  the comparative  index and
Lipper fund rankings.

[mountain graph - data below]

GROWTH OF $10,000 OVER THE LIFE OF THE FUND
Value on 4/30/97

Intermediate-Term Government                $11,655
Lehman Intermediate U.S. Govt. Index        $11,874

           Intermediate-Term Government   Lehman Intermediate U.S. Govt. Index
Mar-94               $10,000                            $10,000
Mar-94                $9,895                             $9,854
Apr-94                $9,851                             $9,790
May-94                $9,854                             $9,797
Jun-94                $9,846                             $9,799
Jul-94                $9,962                             $9,927
Aug-94                $9,979                             $9,956
Sep-94                $9,892                             $9,873
Oct-94                $9,899                             $9,875
Nov-94                $9,854                             $9,831
Dec-94                $9,893                             $9,863
Jan-95               $10,030                            $10,024
Feb-95               $10,216                            $10,217
Mar-95               $10,271                            $10,274
Apr-95               $10,377                            $10,393
May-95               $10,687                            $10,686
Jun-95               $10,749                            $10,754
Jul-95               $10,726                            $10,760
Aug-95               $10,822                            $10,849
Sep-95               $10,905                            $10,922
Oct-95               $11,046                            $11,042
Nov-95               $11,196                            $11,177
Dec-95               $11,323                            $11,287
Jan-96               $11,408                            $11,382
Feb-96               $11,198                            $11,261
Mar-96               $11,103                            $11,210
Apr-96               $11,017                            $11,177
May-96               $10,977                            $11,171
Jun-96               $11,106                            $11,285
Jul-96               $11,136                            $11,320
Aug-96               $11,130                            $11,333
Sep-96               $11,297                            $11,479
Oct-96               $11,501                            $11,667
Nov-96               $11,667                            $11,808
Dec-96               $11,569                            $11,745
Jan-97               $11,622                            $11,789
Feb-97               $11,624                            $11,808
Mar-97               $11,529                            $11,741
Apr-97               $11,655                            $11,874

Past  performance  does not  guarantee  future  results.  Investment  return and
principal  value will fluctuate,  and redemption  value may be more or less than
original cost.

The line representing the fund's total return includes  operating expenses (such
as transaction  costs and management fees) that reduce returns,  while the total
return line of the index does not.

PORTFOLIO AT A GLANCE
                            4/30/97   10/31/96
Number of Securities          28         28
Weighted Average Maturity  4.9 years  5.6 years
Average Duration           3.5 years  3.6 years
Expense Ratio               0.75%*      0.74%

* Annualized.

YIELD AS OF APRIL 30, 1997
                                       30-DAY
                                         SEC
                                        Yield
Intermediate-Term Government            6.03%

Yield is defined in the Glossary on page 25.


Semiannual Report                              Intermediate-Term Government    9


                          INTERMEDIATE-TERM GOVERNMENT

Management Q & A

An  interview  with  Casey  Colton,  a senior  portfolio  manager  on the Benham
Government funds management team.

How did the fund perform?

The fund  matched  its peer group  average.  For the six months  ended April 30,
1997,  the fund had a total  return of 1.35%,  compared  with the 1.34%  average
return  of the 129  "Intermediate  U.S.  Government  Funds"  tracked  by  Lipper
Analytical Services. (See the Total Returns table on the previous page for other
fund performance comparisons.)

How was the fund positioned over the past six months?

We made very few changes to the fund's portfolio during the six-month period. We
shortened its average  maturity and duration a little,  shifting the fund into a
slightly  defensive  position.  Stronger  economic growth in late 1996 and early
1997 prompted  concern about the possibility of a Federal Reserve  interest rate
increase.  The fund's shorter  average  maturity and duration  helped reduce the
negative impact of rising rates on its share price.

We also  maintained  the  fund's  concentration  in  intermediate-term  Treasury
securities,  which made up nearly 75% of the fund's portfolio.  The remainder of
the portfolio was invested in mortgage-backed securities.

[bar graph - data below]

INTERMEDIATE-TERM GOVERNMENT'S 
ONE-YEAR RETURNS SINCE INCEPTION (Periods ended April 30)

        Intermediate-Term Government      Lehman Intermediate Govt. Bond Index
4/30/94            -1.49%                                -2.10%
4/30/95             5.34%                                 6.17%
4/30/96             6.17%                                 7.54%
4/30/97             5.80%                                 6.24%

This graph  illustrates the fund's returns since its inception and compares them
with the index's returns.  The fund's total returns include operating  expenses,
while the index's do not. See page 24 for a definition of the index.
* Return from 3/1/94 to 4/30/94.


10   Intermediate-Term Government                   American Century Investments


                          INTERMEDIATE-TERM GOVERNMENT

What's the attraction of mortgage-backed securities?

Yield   is   the   main    attraction--mortgage-backed    securities   are   the
highest-yielding  government securities  available.  We believe that the current
interest rate environment is favorable for mortgage-backed securities.

Mortgage-backed  securities tend to produce better returns than other government
securities when yield is the most important  component of total return--that is,
when  interest  rates are  relatively  stable.  Even a period of  interest  rate
volatility can be favorable for mortgage-backed securities, as long as there are
no sharp or extended interest rate shifts.

Let's take the past six months as an example.  Interest rates shifted  gradually
throughout the period and only rose slightly  overall.  As a result,  the higher
yields of  mortgage-backed  securities  enabled them to outperform  Treasury and
government agency securities by a wide margin.

Why does the fund continue to avoid government agency securities?

The fund's  small size makes it hard to divide its assets  among many  different
security types. Such fragmentation can reduce the fund's liquidity,  which makes
it hard to respond quickly to changing market conditions.  In addition, we would
be buying such a small amount of government  agency  securities that it would be
difficult to find attractive values. Instead, we try to keep it simple, focusing
the fund's holdings on Treasurys and mortgage-backed securities.

What is your interest rate outlook for the next six months?

Continued strength in the economy will likely lead to higher short-term interest
rates. The U.S. economy picked up steam in the first quarter of 1997, growing at
a 5.8% annual rate. Although that level of growth is probably unsustainable,  we
feel that the pieces  are in place for  continued  healthy  economic  growth.  A
28-year high in consumer  confidence,  the lowest  unemployment rate since 1973,
and solid income growth suggest the possibility of increased  consumer  spending
in the months ahead.

Based on these economic conditions,  we expect the Federal Reserve to maintain a
bias  toward  raising  short-term  interest  rates to slow  growth and  restrict
inflationary  pressures.  One key  factor  to watch is the  labor  market.  With
unemployment at its lowest level in more than 23 years, we believe the risks are
clearly  on the upside  for  higher  wages.  Rising  labor  costs,  which  often
translate into higher prices for consumers,  would likely trigger additional Fed
rate hikes.

[pie charts]

PORTFOLIO COMPOSITION BY SECURITY TYPE (as of 4/30/97)
U.S. Treasury Securities 72%
Mortgage-Backed
Securities 23%
Cash 5%

PORTFOLIO COMPOSITION BY SECURITY TYPE (as of 10/31/96)
U.S. Treasury Securities 71%
Mortgage-Backed
Securities 26%
Cash 3%


Semiannual Report                              Intermediate-Term Government   11


                          INTERMEDIATE-TERM GOVERNMENT

With this  outlook  in mind,  what are your plans for the fund over the next six
months?

We plan to maintain the fund's  slightly  shorter-than-neutral  position.  We'll
also  maintain the fund's  current  weightings  in Treasury and  mortgage-backed
securities. In particular, mortgage-backed securities should continue to perform
well in a gradually rising interest rate environment.

In July,  fund  shareholders  will vote on a proposal to merge the fund into the
Benham Intermediate-Term  Treasury Fund. If this merger is approved, how will it
affect the fund's management?

The  Intermediate-Term  Treasury fund's  investment  objectives and policies are
very similar to those of the Intermediate-Term  Government fund--an intermediate
maturity,  an emphasis on Treasury  securities,  the same fund management  team.
However,  there are some  differences,  most notably that the  Intermediate-Term
Treasury fund focuses almost exclusively on Treasurys.

Shareholders  will also see a couple of other  differences--the  management fees
and  expenses of the new fund will be lower than those of the  Intermediate-Term
Government  fund,  and the size of the new combined  fund will be  substantially
larger.

(PLEASE REVIEW THE PROXY STATEMENT FOR INFORMATION ABOUT THE MERGER,  AND PLEASE
REMEMBER TO VOTE YOUR PROXY.)


12   Intermediate-Term Government                   American Century Investments


                            SCHEDULE OF INVESTMENTS
                          INTERMEDIATE-TERM GOVERNMENT

APRIL 30, 1997 (UNAUDITED)

Principal Amount                ($ in Thousands)                        Value
- --------------------------------------------------------------------------------

U. S. TREASURY SECURITIES
$    1,160    U.S. Treasury Notes, 8.25%,
                7/15/98                                            $  1,189
     2,500    U.S. Treasury Notes, 6.00%,
                8/15/99                                               2,481
     1,270    U.S. Treasury Notes, 8.00%,
                8/15/99                                               1,314
     1,625    U.S. Treasury Notes, 6.875%,
                8/31/99                                               1,643
       485    U.S. Treasury Notes, 7.125%,
                9/30/99                                                 493
       500    U.S. Treasury Notes, 6.125%,
                7/31/00                                                 495
       975    U.S. Treasury Notes, 6.25%,
                8/31/00                                                 969
     1,000    U.S. Treasury Notes, 6.125%,
                9/30/00                                                 989
       725    U.S. Treasury Notes, 5.75%,
                10/31/00                                                709
     1,395    U.S. Treasury Notes, 7.50%,
                11/15/01                                              1,445
       600    U.S. Treasury Notes, 7.50%,
                5/15/02                                                 624
       960    U.S. Treasury Notes, 6.375%,
                8/15/02                                                 952
     1,000    U.S. Treasury Notes, 6.50%,
                8/15/05                                                 985
     2,000    U.S. Treasury Notes, 6.50%,
                10/15/06                                              1,966
       405    U.S. Treasury Bonds, 9.125%,
                5/15/09                                                 456
       830    U.S. Treasury Bonds, 9.25%,
                2/15/16                                               1,019
                                                                   --------
TOTAL U.S. TREASURY SECURITIES--71.7%                                17,729
                                                                   --------
   (Cost $18,110)

MORTGAGE-BACKED SECURITIES(1)
       300    FHLMC REMIC, Series 1576,
                Class PD PAC, 5.50%, 9/15/02                            298
       183    FHLMC  Pool #E00279, 6.50%,
                2/1/09                                                  179
       536    FHLMC Gold Pool #G10418,
                6.50%, 11/1/10                                          522

Principal Amount                ($ in Thousands)                        Value
- --------------------------------------------------------------------------------

$      501    FHLMC Gold Pool #G10461,
                5.50%, 2/1/11                                     $     467
     1,028    FHLMC Gold Pool #E63092,
                6.00%, 3/1/11                                           982
       300    FHLMC REMIC, Series 1684,
                Class D PAC, 5.35%, 11/15/14                            296
       241    FHLMC REMIC, Series 1702-B,
                Class TA PAC, 5.85%, 11/15/17                           239
     1,000    FHLMC REMIC, Series 1684,
                Class F PAC, 5.75%, 8/15/20                             951
     1,485    FNMA REMIC, Series 1993-5,
                Class G PAC 7.15%, 9/25/06                            1,488
       194    GNMA Pool #009314,
                9.75%, 4/20/25                                          208
       172    GNMA Pool #002124,
                9.00%, 11/20/25                                         179
                                                                   --------
TOTAL MORTGAGE-BACKED
SECURITIES--23.5%                                                     5,809
                                                                   --------
   (Cost $5,914)

TEMPORARY CASH INVESTMENTS--4.8%
Repurchase Agreement, J.P. Morgan Securities,
   Inc., (U.S. Treasury obligations), in a
   joint trading account at 5.375%,
   dated 4/30/97, due 5/1/97
   (Delivery value $1,174)                                            1,174
                                                                   --------
   (Cost $1,174)
TOTAL INVESTMENT SECURITIES--100.0%                                 $24,712
   (Cost $25,198)                                                  ========

Notes to Schedule of Investments
FHLMC = Federal Home Loan Mortgage Corporation
FNMA = Federal National Mortgage Association
GNMA = Government National Mortgage Association
(1)  Final maturity indicated.  Expected remaining maturity used for purposes of
     calculating the weighted average portfolio maturity.

See Notes to Financial Statements


Semiannual Report                              Intermediate-Term Government   13


<TABLE>
<CAPTION>
                      STATEMENTS OF ASSETS AND LIABILITIES

APRIL 30, 1997 (UNAUDITED)
                                                                                   SHORT-TERM     INTERMEDIATE-TERM
                                                                                   GOVERNMENT        GOVERNMENT

                                                                     ($ and Shares in Thousands Except Per-Share Amounts)
ASSETS
<S>                                                                                     <C>               <C>
Investment securities, at value (identified cost of
  $324,564 and $25,198, respectively) (Note 3) .................................     $325,133         $24,712
Receivable for capital shares sold .............................................            3              --
Interest receivable ............................................................        3,065             291
                                                                                     --------         -------
                                                                                      328,201          25,003
                                                                                     --------         -------

LIABILITIES
Disbursements in excess of demand deposit cash .................................          930              37
Payable for capital shares redeemed ............................................          170              15
Dividends payable ..............................................................          252              19
Accrued management fees (Note 2) ...............................................          188              15
Other accrued expenses .........................................................            1              --
                                                                                     --------         -------
                                                                                        1,541              86
                                                                                     --------         -------
Net Assets Applicable to Outstanding Shares ....................................     $326,660         $24,917
                                                                                     ========         =======

CAPITAL SHARES, $0.01 PAR VALUE
Authorized .....................................................................      100,000         100,000
                                                                                      =======         =======
Outstanding ....................................................................       34,749           2,600
                                                                                       ======           =====
Net Asset Value Per Share ......................................................        $9.40           $9.58
                                                                                        =====           =====

NET ASSETS CONSIST OF:
Capital (par value and paid in surplus) ........................................     $346,639         $25,387
Accumulated undistributed net realized gain (loss)
  from investment transactions .................................................      (20,548)             16
Net unrealized appreciation (depreciation)
  on investments (Note 3) ......................................................          569            (486)
                                                                                     --------         -------
                                                                                     $326,660         $24,917
                                                                                     ========         =======
</TABLE>
See Notes to Financial Statements


14   Statements of Assets and Liabilities           American Century Investments


<TABLE>
<CAPTION>
                            STATEMENTS OF OPERATIONS

                                                                                   SHORT-TERM     INTERMEDIATE-TERM
                                                                                   GOVERNMENT        GOVERNMENT

                                                                                         ($ in Thousands)
FOR THE SIX MONTHS ENDED APRIL 30, 1997 (UNAUDITED)

INVESTMENT INCOME
Income:
<S>                                                                                   <C>                <C> 
Interest .......................................................................      $10,352            $720
                                                                                     --------         -------
Expenses:
Management fees (Note 2) .......................................................        1,175              90
Directors' fees and expenses ...................................................            2              --
                                                                                     --------         -------
                                                                                        1,177              90
                                                                                     --------         -------
Net investment income ..........................................................        9,175             630
                                                                                     --------         -------

REALIZED AND UNREALIZED GAIN (LOSS)
ON INVESTMENTS (NOTE 3)
Net realized gain (loss) on investments ........................................         (590)             17
Change in net unrealized appreciation (depreciation)
  on investments ...............................................................       (1,844)           (320)
                                                                                     --------         -------
Net realized and unrealized
loss on investments ............................................................       (2,434)           (303)
                                                                                     --------         -------
Net Increase in Net Assets
Resulting from Operations ......................................................     $  6,741            $327
                                                                                     ========         =======
</TABLE>

See Notes to Financial Statements


Semiannual Report                                  Statements of Operations   15


<TABLE>
<CAPTION>
                      STATEMENTS OF CHANGES IN NET ASSETS

                                                                SHORT-TERM                 INTERMEDIATE-TERM
                                                                GOVERNMENT                    GOVERNMENT

                                                                       ($ and Shares in Thousands)
SIX MONTHS ENDED APRIL 30, 1997 (UNAUDITED)
AND YEAR ENDED OCTOBER 31, 1996

Increase (Decrease) in Net Assets                        1997            1996            1997           1996
OPERATIONS
<S>                                                  <C>              <C>             <C>             <C>     
Net investment income .............................  $    9,175       $  19,940       $    630        $  1,331
Net realized gain (loss) on investments ...........        (590)           (339)            17             338
Change in net unrealized appreciation
  (depreciation) on investments ...................      (1,844)         (1,269)          (320)           (720)
                                                       --------        --------        -------         -------
Net increase in net assets resulting
  from operations .................................       6,741          18,332            327             949
                                                       --------        --------        -------         -------

DISTRIBUTIONS TO SHAREHOLDERS
From net investment income ........................      (9,175)        (19,940)          (630)         (1,331)
From net realized gains from
  investment transactions .........................          --              --           (338)           (131)
                                                       --------        --------        -------         -------
Decrease in net assets from distributions .........      (9,175)        (19,940)          (968)         (1,462)
                                                       --------        --------        -------         -------

CAPITAL SHARE TRANSACTIONS
Proceeds from shares sold .........................      46,773          78,893          9,283          19,986
Proceeds from reinvestment of distributions .......       8,689          18,705            937           1,405
Payments for shares redeemed ......................     (76,140)       (137,549)        (9,084)        (18,437)
                                                       --------        --------        -------         -------
Net increase (decrease) in net assets
  from capital share transactions .................     (20,678)        (39,951)         1,136           2,954
                                                       --------        --------        -------         -------
Net increase (decrease) in net assets .............     (23,112)        (41,559)           495           2,441

NET ASSETS
Beginning of period ...............................     349,772         391,331         24,422          21,981
                                                       --------        --------        -------         -------
End of period .....................................    $326,660        $349,772        $24,917         $24,422
                                                       ========        ========        =======         =======

TRANSACTIONS IN SHARES OF THE FUNDS
Sold ..............................................       4,953           8,327            960           2,025
Issued in reinvestment of distributions ...........         921           1,977             97             143
Redeemed ..........................................      (8,066)        (14,531)          (938)         (1,877)
                                                       --------        --------        -------         -------
Net increase (decrease) ...........................      (2,192)         (4,227)           119             291
                                                       ========        ========        =======         =======
</TABLE>
See Notes to Financial Statements

16   Statements of Changes in Net Assets            American Century Investments


                         NOTES TO FINANCIAL STATEMENTS

APRIL 30, 1997 (UNAUDITED)

1. Organization and Summary of Significant Accounting Policies

Organization--American   Century  Mutual  Funds,   Inc.  (the   Corporation)  is
registered under the Investment  Company Act of 1940 as an open-end  diversified
management  investment company.  American Century - Benham Short-Term Government
Fund  (Short-Term)  and American Century - Benham  Intermediate-Term  Government
Fund  (Intermediate-Term)  (the Funds) are two of the seventeen  series of funds
issued by the  Corporation.  The investment  objective of the Funds is to seek a
competitive  level of income.  The Funds  intend to pursue this by  investing in
securities  of the U.S.  government  and its  agencies.  Short-Term  intends  to
maintain   a   weighted   average   maturity   of   three   years  or  less  and
Intermediate-Term  intends to maintain a weighted  average  maturity of three to
ten  years.  On  September  3, 1996,  the Funds  implemented  a  multiple  class
structure  whereby the Funds are authorized to issue two classes of shares:  the
Investor Class and the Advisor Class. The shares  outstanding prior to September
3, 1996,  were  designated as Investor  Class shares.  The two classes of shares
differ  principally in their respective  shareholder  servicing and distribution
expenses and  arrangements.  All shares of each Fund represent an equal pro rata
interest  in the  assets  of the class to which  such  shares  belong,  and have
identical voting, dividend,  liquidation and other rights and the same terms and
conditions,  except for class specific  expenses and exclusive rights to vote on
matters  affecting only  individual  classes.  Sale of the Advisor Class had not
commenced as of the report date. The following significant  accounting policies,
related to all classes of the Funds, are in accordance with accounting  policies
generally accepted in the investment company industry.

Security Valuations--Securities are valued through valuations obtained through a
commercial  pricing  service  or at the mean of the most  recent  bid and  asked
prices. When valuations are not readily available, securities are valued at fair
value as  determined  in  accordance  with  procedures  adopted  by the Board of
Directors.

Security  Transactions--Security  transactions  are  accounted  for on the  date
purchased  or  sold.  Net  realized  gains  and  losses  are  determined  on the
identified cost basis, which is also used for federal income tax purposes.

Investment Income--Interest income is recorded on the accrual basis and includes
amortization of discounts and premiums.

Repurchase  Agreements--The  Funds may enter  into  repurchase  agreements  with
institutions  the  Funds'  investment   manager,   American  Century  Investment
Management,  Inc. (ACIM),  has determined are creditworthy  pursuant to criteria
adopted by the Board of  Directors.  Each  repurchase  agreement  is recorded at
cost.  The  Funds  require  that  the  securities   purchased  in  a  repurchase
transaction be transferred to the custodian in a manner sufficient to enable the
Funds to obtain those  securities in the event of a default under the repurchase
agreement.  ACIM  monitors,  on a  daily  basis,  the  value  of the  securities
transferred  to ensure that the value,  including  interest,  of the  securities
under each repurchase agreement is equal to or greater than amounts owed to each
Fund under each repurchase agreement.

Joint Trading  Account--Pursuant  to an Exemptive Order issued by the Securities
and  Exchange  Commission,  the Funds,  along with other  registered  investment
companies  having   management   agreements  with  ACIM  and  Benham  Management
Corporation, may transfer uninvested cash balances into a joint trading account.
These  balances  are  invested  in one or more  repurchase  agreements  that are
collateralized by U.S. Treasury or Agency obligations.

Income Tax  Status--It is the Funds' policy to distribute all taxable income and
capital gains to shareholders and to otherwise qualify as a regulated investment
company under provisions of the Internal Revenue Code. Accordingly, no provision
has been made for federal income taxes.

Distributions  to  Shareholders--Distributions  from net  investment  income are
declared daily and distributed monthly. Distributions from net realized gains in
excess of available  capital loss carryovers are declared and paid annually.  At
October 31,  1996,  Short-Term  had an  accumulated  net  realized  capital loss
carryover of  $19,957,873  (expiring  1997 through  2002),  which may be used to
offset future taxable gains.

The character of distributions  made during the year from net investment  income
or net  realized  gains may differ  from  their  ultimate  characterization  for
federal income tax purposes.  These differences are primarily due to differences
in the  recognition of income and expense items for financial  statement and tax
purposes.

Supplementary Information--Certain officers and directors of the Corporation are
also officers  and/or  directors,  and as a group,  controlling  stockholders of
American Century  Companies,  Inc., the parent of the  Corporation's  investment
manager,  ACIM,  the  Corporation's  distributor,  American  Century  Investment
Services,  Inc. and the Corporation's  transfer agent, American Century Services
Corporation.


Semiannual Report                             Notes to Financial Statements   17


                         NOTES TO FINANCIAL STATEMENTS

APRIL 30, 1997 (UNAUDITED)

Use of Estimates--  The  preparation of financial  statements in conformity with
generally accepted  accounting  principles requires management to make estimates
and assumptions  that affect the reported  amounts of assets and liabilities and
disclosure of  contingent  assets and  liabilities  at the date of the financial
statements  and the reported  amounts of increases  and  decreases in net assets
from  operations  during the  period.  Actual  results  could  differ from these
estimates.

- --------------------------------------------------------------------------------
2. Transactions with Related Parties

The Corporation  has entered into  Management  Agreements with ACIM that provide
each Fund with  investment  advisory and  management  services in exchange for a
single,  unified management fee per class.  Additional fees apply to the Advisor
Class shares as described in the  prospectus.  The  Agreements  provide that all
expenses of the Funds, except brokerage commissions,  taxes, interest,  expenses
of those directors who are not considered "interested persons" as defined in the
Investment  Company  Act of 1940  (including  counsel  fees)  and  extraordinary
expenses, will be paid by ACIM. The fee is computed daily and paid monthly based
on each Fund's average closing net assets during the previous month.  The annual
management  fee for the  Investor  Class of  Short-Term  is  0.70%.  The  annual
management fee for the Investor Class of Intermediate-Term is 0.75%.

- --------------------------------------------------------------------------------
3. Investment Transactions

The aggregate cost of U.S. Treasury and Agency obligations (excluding short-term
investments)  purchased for the six months ended April 30, 1997,  for Short-Term
and  Intermediate-Term,   totaled  $502,684,404  and  $6,965,313,  respectively.
Proceeds  from  U.S.  Treasury  and  Agency  obligations  (excluding  short-term
investments) sold, for Short-Term and  Intermediate-Term,  totaled  $542,087,900
and $6,607,878, respectively.

As of April 30, 1997, accumulated net unrealized appreciation (depreciation) for
Short-Term  and  Intermediate-Term  was $569,321 and  $(486,056),  respectively,
based on the aggregate  cost of  investments  for federal income tax purposes of
$324,563,795   and   $25,197,742,   respectively.   Accumulated  net  unrealized
appreciation  for Short-Term,  consisted of unrealized  appreciation of $746,940
and unrealized depreciation of $177,619. Accumulated net unrealized depreciation
for  Intermediate-Term,  consisted  of  unrealized  appreciation  of $25,342 and
unrealized depreciation of $511,398.

- --------------------------------------------------------------------------------
4. Corporate Events
<TABLE>

The following name changes became effective January 1, 1997:

                    NEW NAMES                                                     FORMER NAMES
<S>               <C>                                                          <C>
Funds' Issuer:      American Century Mutual Funds, Inc.                           Twentieth Century Investors, Inc.
Funds:              American Century - Benham Short-Term Government Fund          U.S. Governments Short-Term
                    American Century - Benham Intermediate-Term Government Fund   U.S. Governments Intermediate-Term
Parent Company:     American Century Companies, Inc.                              Twentieth Century Companies, Inc.
Distributor:        American Century Investment Services, Inc.                    Twentieth Century Securities, Inc.
Transfer Agent:     American Century Services Corporation                         Twentieth Century Services, Inc.
</TABLE>


18   Notes to Financial Statements                  American Century Investments


<TABLE>
<CAPTION>
                              FINANCIAL HIGHLIGHTS
                             SHORT-TERM GOVERNMENT

 For a Share Outstanding Throughout the Years Ended October 31 (except as noted)

                                      1997(1)       1996         1995         1994        1993(2)       1992(2)

PER-SHARE DATA
Net Asset Value,
<S>                                   <C>          <C>          <C>           <C>          <C>          <C>  
Beginning of Period ................  $9.47        $9.51        $9.27         $9.67        $9.61        $9.41
                                      -----        -----        -----         -----        -----        -----
Income From Investment Operations
  Net Investment Income ............   0.26         0.51         0.52          0.40         0.36         0.44
  Net Realized and Unrealized Gain
  (Loss) on Investment Transactions   (0.07)       (0.04)        0.24         (0.40)        0.06         0.20
                                      -----        -----        -----         -----        -----        -----
  Total From
  Investment Operations ............   0.19         0.47         0.76         --            0.42         0.64
                                      -----        -----        -----         -----        -----        -----
Distributions
  From Net Investment Income .......  (0.26)       (0.51)       (0.52)        (0.40)       (0.36)       (0.44)
                                      -----        -----        -----         -----        -----        -----
Net Asset Value, End of Period .....  $9.40        $9.47        $9.51         $9.27        $9.67        $9.61
                                      =====        =====        =====         =====        =====        =====
  Total Return(3) ..................   1.98%        5.09%        8.42%         0.07%        4.45%        6.85%

RATIOS/SUPPLEMENTAL DATA
Ratio of Operating Expenses
to Average Net Assets .............. 0.70%(4)       0.70%        0.70%         0.81%        1.00%      0.99%(5)
Ratio of Net Investment Income
to Average Net Assets .............. 5.46%(4)       5.39%        5.53%         4.17%        3.73%        4.62%
Portfolio Turnover Rate ............    153%         246%         128%          470%         413%         391%
Net Assets, End
of Period (in thousands) ...........$326,660    $349,772     $391,331      $396,753     $511,981      $569,430

(1)  Six months ended April 30, 1997 (unaudited).

(2)  The data  presented  has been  restated  to give effect to a 10 for 1 stock
     split in the form of a stock dividend that occurred on November 13, 1993.

(3)  Total  return   assumes   reinvestment   of  dividends  and  capital  gains
     distributions, if any. Total returns for periods less than one year are not
     annualized.

(4)  Annualized.

(5)  Expenses  are shown  net of  management  fees  waived  by the  manager  for
     low-balance account fees collected during the period.
</TABLE>

See Notes to Financial Statements


Semiannual Report                                      Financial Highlights   19


<TABLE>
<CAPTION>
                              FINANCIAL HIGHLIGHTS
                          INTERMEDIATE-TERM GOVERNMENT

 For a Share Outstanding Throughout the Years Ended October 31 (except as noted)

                                                                1997(1)       1996         1995         1994(2)

PER-SHARE DATA
Net Asset Value,
<S>                                                              <C>         <C>           <C>         <C>   
Beginning of Period .......................................      $9.84       $10.04        $9.55       $10.00
                                                                 -----        -----        -----        -----
Income From Investment Operations
  Net Investment Income ...................................       0.25         0.54         0.58         0.34
  Net Realized and Unrealized Gain (Loss)
  on Investment Transactions ..............................      (0.12)       (0.14)        0.49        (0.45)
                                                                 -----        -----        -----        -----
Total From Investment Operations ..........................       0.13         0.40         1.07        (0.11)
                                                                 -----        -----        -----        -----
Distributions
  From Net Investment Income ..............................      (0.25)       (0.54)       (0.58)       (0.34)
  From Net Realized Gains on Investment Transactions ......      (0.14)       (0.06)       --           --
                                                                 -----        -----        -----        -----
  Total Distributions .....................................      (0.39)       (0.60)       (0.58)       (0.34)
                                                                 -----        -----        -----        -----
Net Asset Value, End of Period ............................      $9.58        $9.84       $10.04        $9.55
                                                                 =====        =====       ======        =====
  Total Return(3) .........................................       1.35%        4.12%       11.58%       (1.01%)

RATIOS/SUPPLEMENTAL DATA
Ratio of Operating Expenses
to Average Net Assets .....................................     0.75%(4)       0.74%        0.74%      0.75%(4)
Ratio of Net Investment Income
to Average Net Assets .....................................     5.27%(4)       5.50%        5.99%      5.43%(4)
Portfolio Turnover Rate ...................................         30%         112%         137%         205%
Net Assets, End
of Period (in thousands) ..................................     $24,917      $24,422     $21,981       $6,280

(1)  Six months ended April 30, 1997 (unaudited).

(2)  March 1, 1994 (inception) through October 31, 1994.

(3)  Total  return   assumes   reinvestment   of  dividends  and  capital  gains
     distributions, if any. Total returns for periods less than one year are not
     annualized.

(4)  Annualized.
</TABLE>

See Notes to Financial Statements


20   Financial Highlights                           American Century Investments


                         RETIREMENT ACCOUNT INFORMATION

As required by law, any distributions you receive from an IRA and certain 403(b)
distributions  [not  eligible for  rollover to an IRA or to another  403(b)] are
subject to federal income tax withholding at the rate of 10% of the total amount
withdrawn,  unless you elect not to have withholding apply. If you don't want us
to withhold  on this  amount,  you may send us a written  notice not to have the
federal  income tax withheld.  Your written  notice is valid for six months from
the date of  receipt  at  American  Century.  Even if you plan to roll  over the
amount you withdraw to another tax-deferred  account, the withholding rate still
applies to the withdrawn  amount unless we have received a written notice not to
withhold federal income tax within six months prior to the withdrawal.

When  you plan to  withdraw,  you may  make  your  election  by  completing  our
Exchange/  Redemption form or an IRS Form W-4P. Call American Century for either
form.  Your  written  election  is valid  for only six  months  from the date of
receipt at American Century. You may revoke your election at any time by sending
a written notice to us.

Remember,  even if you elect not to have income tax withheld, you are liable for
paying income tax on the taxable portion of your withdrawal. If you elect not to
have income tax withheld or you don't have enough income tax  withheld,  you may
be responsible  for payment of estimated tax. You may incur  penalties under the
estimated  tax rules if your  withholding  and  estimated  tax  payments are not
sufficient.


Semiannual Report                            Retirement Account Information   21


                                     NOTES


22   Notes                                          American Century Investments


                                     NOTES


Semiannual Report                                                     Notes   23


                             BACKGROUND INFORMATION

Investment Philosophy & Policies

The Benham Group offers 42 fixed-income  funds,  ranging from money market funds
to long-term bond funds and including both taxable and tax-exempt funds.

Short-Term  Government  is a  variable-price  bond  fund that  seeks to  provide
interest income by investing in U.S. government and agency securities.  The fund
must maintain a weighted average maturity of 3 years or less.

Intermediate-Term Government is a variable-price bond fund that seeks to provide
interest income by investing in U.S. government and agency securities.  The fund
must maintain a weighted average maturity of 3-10 years.

Comparative Indices

The  indices  listed  below are used in the report to serve as fund  performance
comparisons. They are not investment products available for purchase.

The  Merrill  Lynch  1- to  3-Year  Government  Index  is  based  on  the  price
fluctuations of U.S. Treasury notes with maturities of 1-3 years.

The Lehman Intermediate Government Bond Index is made up of more than 855 issues
with an average  maturity of 3.8 years.  Approximately  87% of the index is U.S.
Treasury issues--the other 13% is U.S. government agency issues.

Lipper Rankings

Lipper Analytical  Services,  Inc. is an independent mutual fund ranking service
that groups funds according to their investment  objectives.  Rankings are based
on average  annual  returns  for each fund in a given  category  for the periods
indicated. Rankings are not included for periods less than one year.

The Lipper categories for the Benham Government funds are:

Short U.S. Government Funds (Short-Term  Government)--funds that invest at least
65% of assets in securities  issued or guaranteed  by the U.S.  government,  its
agencies or instrumentalities  with  dollar-weighted  average maturities of less
than 3 years.

Intermediate U.S. Government Funds  (Intermediate-Term  Government)--funds  that
invest at least 65% of assets in  securities  issued or  guaranteed  by the U.S.
government,  its  agencies or  instrumentalities  with  dollar-weighted  average
maturities of 5-10 years.

PORTFOLIO MANAGEMENT TEAM
Senior Portfolio Managers    Bob Gahagan
                             Casey Colton


24   Background Information                         American Century Investments


                                    GLOSSARY

Returns

o Total  Return  figures  show the overall  percentage  change in the value of a
hypothetical  investment  in  the  fund  and  assume  that  all  of  the  fund's
distributions are reinvested.

o Average Annual Returns  illustrate the annually  compounded returns that would
have produced the fund's cumulative total returns if the fund's  performance had
been  constant  over the  entire  period.  Average  annual  returns  smooth  out
variations  in a fund's  return;  they are not the same as  fiscal  year-by-year
results.  For  fiscal  year-by-year  returns,  please  refer  to the  "Financial
Highlights" on pages 19-20. 

Yields

o 30-day SEC Yield  represents net  investment  income earned by the fund over a
30-day period,  expressed as an annual percentage rate based on the fund's share
price at the end of the 30-day  period.  The SEC yield  should be regarded as an
estimate  of the  fund's  rate of  investment  income,  and it may not equal the
fund's  actual  income  distribution  rate,  the income paid to a  shareholder's
account, or the income reported in the fund's financial statements.

Portfolio Statistics

o Number of Securities--the  number of different  securities held by a fund on a
given date.

o  Weighted  Average  Maturity  (WAM)--a  measurement  of the  sensitivity  of a
fixed-income  portfolio to interest rate changes. WAM indicates the average time
until the securities in the portfolio  mature,  weighted by dollar  amount.  The
longer the WAM, the more interest rate  exposure and  sensitivity  the portfolio
has.

o  Average  Duration--another  measure  of  the  sensitivity  of a  fixed-income
portfolio to interest rate changes.  Duration is a time-weighted  average of the
interest  and  principal  payments  of the  securities  in a  portfolio.  As the
duration  of a portfolio  increases,  so does the impact of a change in interest
rates on the value of the portfolio.

o Expense Ratio--the  operating expenses of the fund,  expressed as a percentage
of average net assets.  Shareholders pay an annual fee to the investment manager
for  investment  advisory  and  management  services.  The expenses and fees are
deducted from fund income, not from each shareholder account. (See Note 2 in the
Notes to Financial Statements.)

Investment Terms

o Basis Point--one  one-hundredth  of a percentage  point (or 0.01%).  100 basis
points  equal one  percentage  point (or 1%).  Basis  points are used to clearly
describe  interest rate changes.  For example,  if a news report  indicates that
interest  rates  rose  by 1%,  does  that  mean 1% of the  previous  rate or one
percentage  point?  It is more accurate to state that interest rates rose by 100
basis points.

o Coupon--the stated interest rate of a security.

o Yield Curve--a graphic representation of the relationship between maturity and
yield  for  fixed-income   securities.   Yield  curve  graphs  plot  lengthening
maturities  along the horizontal axis and rising yields along the vertical axis.
Most "normal"  yield curves start in the lower left corner of the graph and rise
to the upper right corner,  indicating that yields rise as maturities  lengthen.
This   upward   sloping   yield   curve   illustrates   a   normal   risk/return
relationship-more return (yield) for more risk (a longer maturity).  Conversely,
a "flat" yield curve provides little or no extra return for taking on more risk.

Security Types

o Mortgage-Backed  Securities--debt securities that represent ownership in pools
of  mortgage   loans.   Most   mortgage-backed   securities  are  structured  as
"pass-throughs"-the  monthly payments of principal and interest on the mortgages
in the pool are  collected by the bank that is servicing  the  mortgages and are
"passed through" to investors.  While the payments of principal and interest are
considered  secure (many are backed by government agency  guarantees),  the cash
flow is less certain than in other fixed-income investments.  Mortgages that are
paid off early reduce future interest payments from the pool.

o U.S. Government Agency  Securities--debt  securities issued by U.S. government
agencies  (such as the Federal Home Loan Bank and the Federal Farm Credit Bank).
Some  agency  securities  are  backed by the full  faith and  credit of the U.S.
government,  while others are guaranteed only by the issuing agency.  Government
agency  securities  include  discount  notes  (maturing in one year or less) and
medium-term notes, debentures and bonds (maturing in three months to 50 years).

o U.S.  Treasury  Securities--debt  securities  issued by the U.S.  Treasury and
backed by the direct  "full  faith and  credit"  pledge of the U.S.  government.
Treasury  securities  include  bills  (maturing  in one  year  or  less),  notes
(maturing in two to 10 years) and bonds (maturing in more than 10 years).


Semiannual Report                                                  Glossary   25

[american century logo]
American
Century(sm)

P.O. Box 419200
Kansas City, Missouri
64141-6200

Investor Services:
1-800-345-2021 or 816-531-5575

Automated Information Line:
1-800-345-8765

Telecommunications Device for the Deaf:
1-800-634-4113 or 816-444-3485

Fax: 816-340-7962

Internet: www.americancentury.com


AMERICAN CENTURY MUTUAL FUNDS, INC.

Investment Manager
AMERICAN CENTURY INVESTMENT MANAGEMENT


This  report and the  statements  it  contains  are  submitted  for the  general
information of our  shareholders.  The report is not authorized for distribution
to  prospective  investors  unless  preceded  or  accompanied  by  an  effective
prospectus.

American Century Investment Services, Inc.


9706           [recycled logo]
SH-BKT-8697       Recycled
<PAGE>
                               SEMIANNUAL REPORT

                            [american century logo]
                                    American
                                  Century(sm)

                                 April 30, 1997

                                     BENHAM
                                     GROUP

                               Limited-Term Bond
                             Intermediate-Term Bond
                                  Benham Bond

[front cover]

                               TABLE OF CONTENTS

Report Highlights........................................... 1
Our Message to You.......................................... 2
Period Overview............................................. 3
Corporate Credit Review..................................... 4
Limited-Term Bond
     Performance & Portfolio Information.................... 5
     Management Q & A....................................... 6
     Schedule of Investments................................ 9
     Financial Highlights...................................30
Intermediate-Term Bond
     Performance & Portfolio Information....................11
     Management Q & A.......................................12
     Schedule of Investments................................15
     Financial Highlights...................................31
Benham Bond
     Performance & Portfolio Information....................18
     Management Q & A.......................................19
     Schedule of Investments................................22
     Financial Highlights...................................32
Statements of Assets and Liabilities........................24
Statements of Operations....................................25
Statements of Changes in Net Assets.........................26
Notes to Financial Statements...............................27
Retirement Account Information..............................33
Background Information
     Investment Philosophy & Policies.......................36
     Comparative Indices....................................36
     Lipper Rankings........................................36
     Portfolio Management Team..............................36
     Credit Research Team...................................36
Glossary....................................................37

American Century  Investments offers you nearly 70 fund choices covering stocks,
bonds, money markets,  specialty investments and blended portfolios. To help you
find the funds that may meet your needs, we have divided  American Century funds
into three groups based on investment style and objectives.  These groups, which
appear below, are designed to help simplify your fund decisions.

                  American Century Investments--Family of Funds

     BENHAM GROUP           AMERICAN CENTURY GROUP       TWENTIETH CENTURY GROUP

  MONEY MARKET FUNDS          ASSET ALLOCATION &
 GOVERNMENT BOND FUNDS        BALANCED FUNDS                U.S. GROWTH FUNDS
DIVERSIFIED BOND FUNDS   CONSERVATIVE EQUITY FUNDS         INTERNATIONAL FUNDS
 MUNICIPAL BOND FUNDS         SPECIALTY FUNDS

   Limited-Term Bond
Intermediate-Term Bond
      Benham Bond

We welcome your comments or questions about this report. 
See the back cover for ways to contact us by mail, phone or e-mail.

Twentieth Century and the Benham Group are registered marks of American
Century Services Corporation and Benham Management Corporation, respectively.
American Century is a service mark of American Century Services Corporation.


                                                    American Century Investments


                               REPORT HIGHLIGHTS

Period Overview

o    U.S.  economic  growth  accelerated  during the six months  ended April 30,
     1997. Despite strong economic growth, inflation remained relatively tame.

o    The Federal  Reserve raised  short-term  interest rates in late March in an
     attempt to pre-empt inflation going forward.

o    The combination of strong economic growth and rising wage pressures  caused
     bond yields to rise during the period.

o    The  relatively  high  yields  offered  by  mortgage-backed  and  corporate
     securities  helped them  outperform  both  Treasury and  government  agency
     securities.

Corporate Credit Review

o    A strong U.S. economy led to improved  corporate  credit quality.  Specific
     sectors  that  benefited  from  upgrades  were  energy,  airlines and basic
     industrials.

o    We  continue to monitor  several  trends with  important  implications  for
     corporate  credit  quality,  including  share  repurchases  and mergers and
     acquisitions.

o    Deregulation also presents new concerns for corporate credit,  particularly
     in the electric utility and telecommunications industries.

Limited-Term Bond

o    The fund  performed in line with its Lipper  peer-group  average during the
     six months ended April 30, 1997.

o    We positioned  the fund  defensively,  shortening its duration and weighted
     average  maturity.  This  positioning  benefited the fund as interest rates
     rose overall during the period.

o    Going forward, we expect strong economic growth and tight labor markets may
     push interest rates higher in the coming months.

Intermediate-Term Bond

o    The fund outperformed its Lipper  peer-group  average during the six months
     ended April 30, 1997.

o    We invested the majority of the fund's assets in  high-yielding  securities
     such as corporate, mortgage- and asset-backed bonds.

o    Going forward, we'll likely maintain the fund's defensive position while we
     concentrate on adding high-yielding securities at attractive values.

Benham Bond

o    The fund  performed  well  relative to its Lipper peer group during the six
     months ended April 30, 1997.

o    We made few changes to the fund's duration and average  maturity during the
     period.

o    Going  forward,  we'll  likely  continue to manage the fund's  duration and
     average maturity conservatively.

                               Limited-Term Bond
                      Total Returns:      AS OF 4/30/97
                         6 Months                2.20%*
                         1 Year                   5.78%
                      Net Assets:          $9.3 million
                         (AS of 4/30/97)
                      Inception Date:            3/1/94
                      Ticker Symbol:                N/A


                             Intermediate-Term Bond
                      Total Returns:      AS OF 4/30/97
                         6 Months                1.57%*
                         1 Year                   6.30%
                      Net Assets:         $17.2 million
                         (AS of 4/30/97)
                      Inception Date:            3/1/94
                      Ticker Symbol:              TWITX


                                  Benham Bond
                      Total Returns:      AS OF 4/30/97
                         6 Months                1.45%*
                         1 Year                   6.65%
                      Net Assets:        $128.2 million
                         (AS of 4/30/97)
                      Inception Date:            3/2/87
                      Ticker Symbol:              TWLBX

                      * Not annualized.


                 Many of the investment terms in this report are
                       defined in the Glossary on page 37.


Semiannual Report                                         Report Highlights    1


                               OUR MESSAGE TO YOU

              [photo of James E. Stowers III and James M. Benham]

April 30,  1997,  marked the end of an eventful  period for our company and U.S.
bond markets. Bonds posted modest returns as accelerating first-quarter economic
growth sent bond yields higher. Overall, mortgage-backed securities outperformed
corporate,  government  agency and Treasury bonds. In the following  pages,  our
investment  management team provides further details about these markets and how
your fund was managed during the period.

In January,  nearly two years of integration  between  Twentieth Century and The
Benham  Group   culminated  when  we  began  serving  you  as  American  Century
Investments.  Under this new name we have  combined  our  offerings of nearly 70
funds.

The new name also introduces three new groupings for the funds--the Benham Group
(money market and bond funds),  the American  Century  Group (asset  allocation,
balanced,  conservative  equity and specialty  funds) and the Twentieth  Century
Group (aggressive  growth and international  equity funds). The Diversified Bond
funds have joined the Benham  Group  because  their  investment  goals match key
attributes of that group.

By now,  you should have  received a proxy  statement  and  ballot;  we strongly
encourage  you to read it carefully  and take part in the proxy vote if you have
not already done so.

In  reviewing  this report,  you may notice some  changes.  Based on  investors'
feedback,  our  shareholder  reports have been  redesigned  with added features,
including a report  summary,  a glossary,  more charts and graphs,  and expanded
management Q & A and background information sections.

These are  examples  of how we  continue  working  to  provide  information  and
services  that are useful and  convenient  to  investors  in our funds.  We look
forward to sharing other helpful changes with you.

/s/James E. Stowers III                     /s/James M. Benham
James E. Stowers III                        James M. Benham
President and Chief Executive Officer       Vice Chairman
American Century Companies                  American Century Companies


2    Our Message to You                             American Century Investments


                                PERIOD OVERVIEW

U.S. Economy

U.S.  economic  growth  accelerated  during the six months ended April 30, 1997.
After moderating throughout the summer of 1996, economic growth rebounded in the
fourth quarter as strong employment  growth,  increased  consumer spending and a
robust housing market fueled an annualized growth rate of 3.8%. The U.S. economy
continued to pick up speed in the first quarter of 1997, surging ahead at a 5.8%
annual rate.

Although  such  a  strong  level  of  economic  growth  has  historically   been
accompanied by rising prices,  inflation remained relatively  tame--the consumer
price  index rose at an annual  rate of 3.2% during the  six-month  period.  But
recent  evidence of  increasing  wage  pressures--which  are often  passed on to
consumers  in the form of  higher  prices--led  the  Federal  Reserve  to make a
pre-emptive  strike against  inflation by raising  short-term  interest rates in
March. The Fed raised its federal funds rate target (the overnight  lending rate
targeted  by the Fed for large  loans  between  commercial  banks) from 5.25% to
5.50%.

U.S. Bond Market

U.S. fixed-income securities produced modest returns during the six months ended
April 30.  Rising  interest  rates (see the graph  above)  caused bond prices to
fall, but the interest income paid out to bondholders generally offset the price
declines.  Short-term  securities,  which usually suffer less price depreciation
than  longer-term  securities when interest rates rise, were the best performers
during the period. For example, the two-year Treasury note posted a 2.38% return
for the six-month period, while the 30-year Treasury bond returned -0.47%.

Early in the  six-month  period,  bond  yields  fell (and bond  prices  rose) in
response to low inflation and market  perceptions of slow economic  growth going
forward.  But by the beginning of 1997, stronger economic growth and rising wage
pressures  rekindled concerns about inflation.  As a result,  bond yields soared
throughout the first quarter.  The 30-year Treasury bond yield, which fell to as
low as 6.35% in December,  climbed to 7.10% by the end of March. The bond market
vacillated  in  April,  rallying  toward  the end of the  month  on  encouraging
inflation news.

Mortgage-backed  securities were the top-performing  fixed-income  sector during
the  six-month  period,  followed by corporate,  government  agency and Treasury
securities.  With bond prices  declining  slightly  overall,  yield was the most
significant  contributor to bond returns.  Corporate and mortgage-backed  issues
tend to have  relatively  high  yields,  while  government  agency and  Treasury
securities tend to have lower yields.

[line graph - data below]

TREASURY YIELD CURVES

Years to Maturity       4/30/97         10/31/96
1                       5.88             5.404
2                       6.27             5.732
3                       6.39             5.86
4                       6.47             5.89
5                       6.56             6.07
6                       6.6              6.105
7                       6.64             6.14
8                       6.66             6.207
9                       6.68             6.274
10                      6.7              6.341
11                      6.733            6.3758
12                      6.766            6.4106
13                      6.799            6.4454
14                      6.832            6.4802
15                      6.865            6.515
16                      6.898            6.55
17                      6.931            6.585
18                      6.964            6.62
19                      6.997            6.655
20                      7.03             6.69
21                      7.022            6.685
22                      7.014            6.68
23                      7.006            6.675
24                      6.998            6.67
25                      6.99             6.665
26                      6.982            6.6602
27                      6.974            6.6554
28                      6.966            6.6506
29                      6.958            6.6458
30                      6.95             6.641
Source: Bloomberg Financial Markets


Semiannual Report                                           Period Overview    3


                            CORPORATE CREDIT REVIEW

Corporate  credit  continued  to improve  during the six months  ended April 30,
1997. A seventh  consecutive  year of economic  growth led to healthier  balance
sheets for many U.S. corporations.  Steady corporate earnings growth contributed
to a record number of corporate credit rating upgrades.

Specific sectors that benefited from the upgrade trend were energy, airlines and
basic  industrials.  In the financial  sector,  banks remained stable and strong
after  several years of credit  upgrades.  Credit  improved in these  industries
because  of  increased   efficiencies,   lower  debt  levels  and  the  sale  of
underperforming assets.

We continue  to monitor a trend  toward  share  repurchases  that has  important
implications for corporate credit quality.  Share repurchases  utilize cash flow
that could have been used to retire  debt,  and they reduce a  company's  equity
base,  resulting  in increased  leverage.  (Leverage is a measure of a company's
debt relative to its equity.  The higher a company's  debt-to-equity  ratio, the
greater its leverage.) Rather than reduce their debt burden,  many companies are
opting to increase shareholder value by repurchasing stock.

We also  continue to weigh the possible  effect of mergers and  acquisitions  on
corporate credit quality.  Mergers pose specific credit  considerations  because
the acquisitions  themselves may result in more highly leveraged  companies.  On
the other hand,  mergers and  acquisitions  can be positive from a  debtholder's
perspective because aggregation can add diversity to the business,  improve cash
flows and generate greater long-term efficiencies.

Banking is a good example of an industry that has benefited from  consolidation.
Increased efficiencies and merger-related expense savings have played a big part
in the recent trend toward credit upgrades in this sector.

Deregulation   remains  a  key   consideration   in  the  electric  utility  and
telecommunications industries. Utilities will need to become more efficient in a
newly  competitive  environment.  Telecommunications  companies  are also  going
through a new wave of competition after passage of the Telecommunications Reform
Act in 1996.

We use a team-oriented  approach to stay abreast of these  developing  corporate
credit trends.  We emphasize team analysis by  professionals  with experience in
industries  to which we have  exposure.  Our  analytical  team members  focus on
specific industries to greater utilize their industry expertise and add value to
our funds.

[line graph - data below]

IMPROVING CORPORATE CREDIT QUALITY

              Downgrades             Upgrades
'87               189                   102
'88               237                   138
'89               339                   138
'90               433                   98
'91               350                   119
'92               227                   136
'93               154                   163
'94               160                   183
'95               221                   205
'96               184                   283

Source: Moody's Investors Service


4    Corporate Credit Review                        American Century Investments

<TABLE>
<CAPTION>
                               LIMITED-TERM BOND

                                                                                AVERAGE ANNUAL RETURNS
                                                          6 MONTHS       1 YEAR         3 YEARS    LIFE OF FUND
TOTAL RETURNS AS OF APRIL 30, 1997
<S>                                                         <C>           <C>            <C>           <C>  
Limited-Term Bond ......................................    2.20%         5.78%          5.86%         5.17%
Merrill Lynch 1- to 5-Year Govt./Corp. Index ...........    2.08%         6.23%          6.59%         5.73%
Average Short Investment-Grade Debt Fund(1) ............    2.19%         5.80%          5.78%         5.53%(2)
Fund's Ranking Among
Short Investment-Grade Debt Funds(1) ...................     --       46 out of 96   28 out of 71 32 out of 67(2)

(1)  According to Lipper Analytical Services.

(2)  Data since  3/31/94,  the date nearest the fund's  inception for which data
     are available. Inception date was March 1, 1994.
</TABLE>

See pages 36-37 for more information  about returns,  the comparative  index and
Lipper fund rankings.

[mountain graph - data below]

GROWTH OF $10,000 OVER THE LIFE OF THE FUND
Value on 4/30/97

Limited Bond $11,730
Merrill Lynch 1- to 5-Year Govt./Corp. Index $11,930

            Limited Bond       Merrill Lynch 1- to 5-Year Govt./Corp. Index

Mar-94        $10,000                            $10,000
Mar-94         $9,933                             $9,909
Apr-94         $9,888                             $9,851
May-94         $9,887                             $9,865
Jun-94         $9,907                             $9,885
Jul-94         $9,999                             $9,990
Aug-94        $10,030                            $10,026
Sep-94         $9,990                             $9,974
Oct-94         $9,992                             $9,988
Nov-94         $9,953                             $9,935
Dec-94         $9,980                             $9,961
Jan-95        $10,102                            $10,113
Feb-95        $10,230                            $10,285
Mar-95        $10,291                            $10,347
Apr-95        $10,393                            $10,454
May-95        $10,582                            $10,699
Jun-95        $10,621                            $10,763
Jul-95        $10,650                            $10,791
Aug-95        $10,722                            $10,865
Sep-95        $10,795                            $10,927
Oct-95        $10,881                            $11,035
Nov-95        $10,986                            $11,152
Dec-95        $11,072                            $11,252
Jan-96        $11,169                            $11,353
Feb-96        $11,108                            $11,274
Mar-96        $11,095                            $11,242
Apr-96        $11,089                            $11,231
May-96        $11,119                            $11,238
Jun-96        $11,194                            $11,335
Jul-96        $11,236                            $11,376
Aug-96        $11,256                            $11,403
Sep-96        $11,365                            $11,528
Oct-96        $11,477                            $11,688
Nov-96        $11,577                            $11,802
Dec-96        $11,562                            $11,772
Jan-97        $11,616                            $11,824
Feb-97        $11,644                            $11,845
Mar-97        $11,640                            $11,817
Apr-97        $11,730                            $11,930


Past  performance  does not  guarantee  future  results.  Investment  return and
principal  value will fluctuate,  and redemption  value may be more or less than
original cost.

The line representing the fund's total return includes  operating expenses (such
as transaction  costs and management fees) that reduce returns,  while the total
return line of the index does not.

PORTFOLIO AT A GLANCE
                            4/30/97   10/31/96
Number of Securities          34         29
Weighted Average Maturity  1.8 years  2.1 years
Average Duration           1.6 years  1.7 years
Expense Ratio               0.69%*      0.68%

* Annualized.

YIELD AS OF APRIL 30, 1997
                                       30-DAY
                                         SEC
                                        Yield

Limited-Term Bond                       5.82%

Yield is defined in the Glossary on page 37.


Semiannual Report                                         Limited-Term Bond    5


                               LIMITED-TERM BOND

Management Q & A

An interview  with Jeff Houston,  a portfolio  manager on the  Diversified  Bond
funds management team.

How did the fund perform?

The fund  performed  in line with its peers.  For the six months ended April 30,
1997, the fund returned 2.20%, compared with the 2.19% average return of the 105
"Short  Investment-Grade Debt Funds" tracked by Lipper Analytical Services. (See
the  Total  Returns  table on the  previous  page  for  other  fund  performance
comparisons.)   The  fund's   relatively  low  expenses  and  our   disciplined,
team-oriented management approach contributed to the fund's performance.

How was the fund positioned?

We maintained a defensive posture,  shortening the fund's duration slightly from
1.7 years at the  beginning  of the  period to 1.6 years by the end of April.  A
shorter  duration  benefited the fund as bond prices declined overall during the
period.  (Duration is a measure of portfolio  sensitivity to changes in interest
rates.  The shorter a fund's  duration,  the less dramatic  movements in its net
asset value tend to be when rates change.)

We  concentrated  on adding  value to the fund by keeping  the  majority  of its
assets in higher-yielding  securities,  such as corporate debt and mortgage- and
asset-backed  securities.  Mortgage-backed  securities  were the  top-performing
fixed-income  sector for the period,  thanks in large part to their high yields.

[bar graph - data below]

LIMITED-TERM BOND'S ONE-YEAR RETURNS SINCE INCEPTION (Periods ended April 30)

          Limited-Term Bond    Merrill Lynch 1- to 5-Year Govt./Corp. Index

4/30/94*       -1.12%                             -1.49%
4/30/95         5.11%                              6.12%
4/30/96         6.69%                              7.43%
4/30/97         5.78%                              6.23%

This graph  illustrates the fund's returns since its inception and compares them
with the index's returns.  The fund's total returns include operating  expenses,
while the index's do not.  See page 36 for a definition  of the index.  * Return
from the fund's 3/1/94 inception date to 4/30/94.


6    Limited-Term Bond                              American Century Investments


                               LIMITED-TERM BOND

Corporate  securities  also  performed  well  as the  difference  in  yield,  or
"spread," between Treasurys and corporate debt continued to narrow.

Why are spreads between corporate and Treasury securities declining?

Corporate bonds typically offer higher yields than Treasury debt as compensation
for their  greater  credit risk.  However,  the strong  economy and  disciplined
fiscal  management  have  helped  improve   corporate  balance  sheets.   That's
translated  into credit upgrades and higher prices for corporate debt. The rapid
pace  of  stock-financed   corporate  mergers  and  acquisitions  also  improved
corporate   credit  by   encouraging   economies   of  scale   and   eliminating
inefficiencies.  Heavy demand from mutual fund managers and foreign  buyers also
helped increase prices and lower yields on corporate bonds.

You  mentioned  that  you've  been  buying  asset-backed  securities.  What  are
asset-backed securities and why are they so attractive?

Asset-backed  securities are debt securities that represent  ownership in a pool
of assets.  Auto loans and credit cards are good  examples of types of debt that
are  commonly  packaged  as  asset-backed  securities.  Asset-backed  securities
generally  have very high credit  quality  because  they  usually  carry  credit
enhancements,   such  as  bond   insurance.   The   securities  are  also  often
overcollateralized--they  contain  more assets than are  required to pay off the
debt. Another attraction of asset-backed  securities is that they typically have
high yields  relative to their credit  quality.  Consistent with our approach to
managing credit risk, we've added specialists in asset-backed  securities to our
corporate credit research staff.

You  increased  the fund's  holdings  of  corporate  bonds  rated BBB during the
period. Why?

Selectively  adding  corporate  securities  rated BBB proved to be a good way to
enhance the fund's  yield and boost  returns.  We worked very  closely  with our
corporate  credit research team to identify  securities we felt were undervalued
by virtue of their credit rating or market valuation. The trend toward improving
corporate  credit  resulted  in rating  upgrades  and  tighter  spreads  between
corporate  bonds rated AAA and BBB.  Rating  upgrades  benefit the fund  because
upgraded securities typically rise in value.

What's your outlook for interest rates over the next six months?

We expect the U.S.  Federal  Reserve's  interest  rate policy  decisions  in the
coming months to hinge on two factors:  economic  growth and labor costs.  While
the current economic  expansion--now in its seventh year--is  remarkable for its
lack of  inflation,  we don't  think  the Fed  will  sit idly by if the  economy

[pie charts]

PORTFOLIO COMPOSITION BY SECURITY TYPE (as of 4/30/97)
U.S. Treasury Securities 33%
Corporate Bonds 33%
Asset-Backed Securities 13%
Cash 13%
Mortgage-Backed Securities 6%
U.S. Government Agency
Securities 2%

PORTFOLIO COMPOSITION BY SECURITY TYPE (as of 10/31/96)
U.S. Treasury Securities 40%
Corporate Bonds 36%
Asset-Backed Securities 10%
Mortgage-Backed Securities 7%
Sovereign Governments &
Agencies 4%
Cash 3%


Semiannual Report                                         Limited-Term Bond    7


                               LIMITED-TERM BOND

continues to grow above trend. We think the economy will slow to a more moderate
pace in the coming months.  But if that doesn't happen, the Fed will likely feel
compelled to raise rates.

The Fed is concerned that rising labor costs will push inflation  higher.  Labor
costs are an important  consideration  for future inflation because they account
for  about   two-thirds  of  total  business   costs.   Improvements  in  worker
productivity  and  savings on health  care and  benefits  have so far kept labor
costs in check, but they may have run their course.

In addition, the unemployment rate fell to a 23-year low of 4.9% in April. Labor
market  capacity is  generally  defined as being tight at these  levels.  To the
extent that capacity is  stretched,  prices for labor will be pressured to rise.
Higher wages can be expected to boost consumer  spending,  which drives economic
growth. As a result,  we expect the Fed to continue to hike short-term  interest
rates  unless the economy  slows.  But because  interest  rates are already at a
level that should inhibit growth,  we don't think rates are headed  dramatically
higher.

With that outlook in mind, how will you manage the fund going forward?

We'll likely maintain the fund's  defensive  posture in the near term,  taking a
conservative  approach to managing its duration  and average  maturity.  We will
also continue to try to boost returns by purchasing  high-yielding securities at
what we feel are attractive values.

[pie charts]

PORTFOLIO COMPOSITION BY CREDIT RATING (as of 4/30/97)
AAA 67%
A 13%
BBB 20%

PORTFOLIO COMPOSITION BY CREDIT RATING (as of 10/31/96)
AAA 60%
AA 4%
A 19%
BBB 17%

8    Limited-Term Bond                              American Century Investments


                            SCHEDULE OF INVESTMENTS
                               LIMITED-TERM BOND

APRIL 30, 1997 (UNAUDITED)

Principal Amount                ($ in Thousands)                        Value
- --------------------------------------------------------------------------------

U.S. TREASURY SECURITIES
$    1,100    U.S. Treasury Notes, 6.125%,
                3/31/98                                              $1,102
       800    U.S. Treasury Notes, 6.00%,
                9/30/98                                                 799
       300    U.S. Treasury Notes, 5.625%,
                11/30/98                                                298
       500    U.S. Treasury Notes, 5.875%,
                1/31/99                                                 497
       100    U.S. Treasury Notes, 5.00%,
                2/15/99                                                  98
       300    U.S. Treasury Notes, 6.25%,
                3/31/99                                                 300
                                                                     ------
TOTAL U.S. TREASURY SECURITIES--33.4%                                 3,094
                                                                     ------
   (Cost $3,096)

U.S. GOVERNMENT AGENCY SECURITIES--2.1%
       193    FHLB, 6.21%, 3/29/99                                      193
                                                                     ------
   (Cost $192)

MORTGAGE-BACKED SECURITIES(1)
       297    General Electric Capital Mortgage
                Services, Inc. REMIC, Series
                1997-3, Class A14, 7.50%,
                4/25/27                                                 300
        60    FHLMC REMIC, Series 1239,
                Class E PAC, 6.80%, 1/15/16                              60
       193    FNMA REMIC, Series 1991-21,
                Class G PAC, 6.00%, 12/25/19                            192
                                                                     ------
TOTAL MORTGAGE-BACKED
SECURITIES--6.0%                                                        552
                                                                     ------
   (Cost $551)

ASSET-BACKED SECURITIES(1)
       200    First Merchants Auto Receivables
                Corp., Series 1996-B, Class A2,
                6.80%, 5/15/01                                          202
       250    FNMA Whole Loan, Series
                1995-W1, Class A6, 8.10%,
                4/25/25                                                 257

Principal Amount                ($ in Thousands)                        Value
- --------------------------------------------------------------------------------

$      200    NationsBank Auto Owner Trust,
                Series 1996-A, Class B1, 6.75%,
                6/15/01                                             $   201
       200    The Money Store Home Equity
                Trust, Series 1996-D, Class A3,
                6.295%, 11/15/11                                        199
       200    UCFC Home Equity Loan, Series
                1996-B1, Class A2, 7.075%,
                4/15/10                                                 202
       150    UCFC Home Equity Loan, Series
                1996-D1, Class A4, 6.776%,
                2/15/16                                                 148
                                                                     ------
TOTAL ASSET-BACKED SECURITIES--13.0%                                  1,209
                                                                     ------
   (Cost $1,206)

CORPORATE BONDS
BANKING--6.5%
       200    Chase Manhattan Corp., 8.80%,
                2/1/00                                                  200
       200    Golden West Financial Corp.,
                9.15%, 5/23/98                                          206
       200    MBNA Corp., 6.875%, 10/1/99                               201
                                                                     ------
                                                                        607
                                                                     ------
FINANCIAL SERVICES--17.3%
       200    Comdisco, Inc., 6.375%, 11/30/01                          195
       100    Commercial Credit Co.,
                5.75%, 7/15/00                                           97
       200    Ford Motor Credit Co., 7.75%,
                10/1/99                                                 205
       200    Franchise Finance Corp., 7.00%,
                11/30/00                                                198
       250    General Motors Acceptance Corp.,
                MTN, 7.30%, 2/2/98                                      252
       250    Lehman Brothers Holdings, Inc.,
                6.625%, 11/15/00                                        247
       200    Paine Webber Group Inc., MTN,
                7.96%, 4/28/00                                          206
       200    Salomon Brothers Inc., MTN, 7.59%,
                1/28/00                                                 203
                                                                     ------
                                                                      1,603
                                                                     ------

See Notes to Financial Statements


Semiannual Report                                         Limited-Term Bond    9


                            SCHEDULE OF INVESTMENTS
                               LIMITED-TERM BOND

APRIL 30, 1997 (UNAUDITED)

Principal Amount                ($ in Thousands)                        Value
- --------------------------------------------------------------------------------

PAPER & FOREST PRODUCTS--2.2%
$      200    Boise Cascade Co., 7.375%,
                8/1/97                                              $   200
                                                                     ------
REAL ESTATE--3.2%
       300    Price REIT, Inc. (The), 7.25%,
                11/1/00                                                 300
                                                                     ------
RETAIL (GENERAL MERCHANDISE)--1.2%
       100    Dayton Hudson Co., 9.25%,
                3/1/01                                                  107
                                                                     ------
UTILITIES--2.1%
       200    Cincinnati Gas & Electric Co.,
                5.80%, 2/15/99                                          198
                                                                     ------
TOTAL CORPORATE BONDS--32.5%                                          3,015
                                                                     ------
   (Cost $3,017)

TEMPORARY CASH INVESTMENTS
   Repurchase Agreement, Goldman Sachs & Co.,
      Inc., (U.S. Treasury obligations), in a joint
      trading account at 5.29%, dated 4/30/97,
      due 5/1/97 (Delivery value $274)                                  274
   Repurchase Agreement, J.P. Morgan Securities,
      Inc., (U.S. Treasury obligations), in a joint
      trading account at 5.375%, dated 4/30/97,
      due 5/1/97 (Delivery value $467)                                  467
   467,000 Units of Participation in Chase Vista
      Prime Money Market Fund (Institutional
      Shares), 5.47%, 5/1/97                                            467
                                                                     ------
TOTAL TEMPORARY CASH
INVESTMENTS--13.0%                                                    1,208
                                                                     ------
   (Cost $1,208)
TOTAL INVESTMENT SECURITIES--100.0%                                  $9,271
                                                                     ======
   (Cost $9,270)

Notes to Schedule of Investments
FHLB = Federal Home Loan Bank
FHLMC = Federal Home Loan Mortgage Corporation
FNMA = Federal National Mortgage Association
MTN = Medium Term Note
(1)  Final maturity indicated.  Expected remaining maturity used for purposes of
     calculating the weighted average portfolio maturity.

See Notes to Financial Statements


10   Limited-Term Bond                              American Century Investments


<TABLE>
<CAPTION>
                             INTERMEDIATE-TERM BOND

                                                                                AVERAGE ANNUAL RETURNS
                                                          6 MONTHS       1 YEAR         3 YEARS    LIFE OF FUND
TOTAL RETURNS AS OF APRIL 30, 1997
<S>                                                         <C>           <C>            <C>           <C>  
Intermediate-Term Bond ..................................   1.57%         6.30%          6.62%         5.53%
Lehman Intermediate Govt./Corp. Index ...................   1.74%         6.41%          6.92%         5.76%
Average Intermediate Investment-Grade Debt Fund(1) ......   1.49%         6.46%          6.79%         6.26%(2)
Fund's Ranking Among Intermediate
Investment-Grade Debt Funds(1) ..........................    --      83 out of 181  60 out of 116 56 out of 114(2)

(1) According to Lipper Analytical Services.
(2) Data since 3/31/94, the date nearest the fund's inception for which data are
    available. Inception date was March 1, 1994.
</TABLE>

See pages 36-37 for more information  about returns,  the comparative  index and
Lipper fund rankings.

[mountain graph - data below]

GROWTH OF $10,000 OVER THE LIFE OF THE FUND
Value on 04/30/97

Intermediate-Term Bond     $11,857
Lehman Intermediate Govt./Corp. Index       $11,939
 ..................
         Intermediate-Term Bond    Lehman Intermediate Govt./Corp. Index
Mar-94          $10,000                          $10,000
Mar-94           $9,856                           $9,835
Apr-94           $9,784                           $9,768
May-94           $9,798                           $9,775
Jun-94           $9,800                           $9,776
Jul-94           $9,926                           $9,917
Aug-94           $9,950                           $9,947
Sep-94           $9,881                           $9,856
Oct-94           $9,876                           $9,855
Nov-94           $9,840                           $9,811
Dec-94           $9,879                           $9,845
Jan-95          $10,014                          $10,011
Feb-95          $10,200                          $10,219
Mar-95          $10,264                          $10,277
Apr-95          $10,369                          $10,403
May-95          $10,701                          $10,717
Jun-95          $10,753                          $10,789
Jul-95          $10,743                          $10,790
Aug-95          $10,863                          $10,888
Sep-95          $10,949                          $10,967
Oct-95          $11,080                          $11,089
Nov-95          $11,232                          $11,234
Dec-95          $11,372                          $11,352
Jan-96          $11,472                          $11,449
Feb-96          $11,286                          $11,315
Mar-96          $11,215                          $11,258
Apr-96          $11,154                          $11,218
May-96          $11,129                          $11,209
Jun-96          $11,253                          $11,328
Jul-96          $11,277                          $11,362
Aug-96          $11,264                          $11,371
Sep-96          $11,448                          $11,529
Oct-96          $11,674                          $11,733
Nov-96          $11,861                          $11,888
Dec-96          $11,743                          $11,812
Jan-97          $11,802                          $11,858
Feb-97          $11,833                          $11,881
Mar-97          $11,713                          $11,799
Apr-97          $11,857                          $11,939

Past  performance  does not  guarantee  future  results.  Investment  return and
principal  value will fluctuate,  and redemption  value may be more or less than
original cost.

The line representing the fund's total return includes  operating expenses (such
as transaction  costs and management fees) that reduce returns,  while the total
return line of the index does not.

PORTFOLIO AT A GLANCE
                            4/30/97   10/31/96
Number of Securities          60         49
Weighted Average Maturity  6.0 years  6.4 years
Average Duration           4.0 years  4.0 years
Expense Ratio               0.75%*      0.74%

* Annualized.

YIELD AS OF APRIL 30, 1997
                                       30-DAY
                                         SEC
                                        Yield

Intermediate-Term Bond                  6.41%

Yield is defined in the Glossary on page 37.


Semiannual Report                                    Intermediate-Term Bond   11


                             INTERMEDIATE-TERM BOND

Management Q & A

An interview  with Jeff Houston,  a portfolio  manager on the  Diversified  Bond
funds management team.

How did the fund perform?

The fund  performed  well relative to its peers.  For the six months ended April
30, 1997, the fund returned 1.57%, compared with the 1.49% average return of the
190  "Intermediate  Investment-Grade  Debt Funds"  tracked by Lipper  Analytical
Services.  (See the Total  Returns  table on the  previous  page for other  fund
performance   comparisons.)   The  fund's   relatively   low  expenses  and  our
disciplined, team-oriented management approach helped the fund's performance.

How was the fund positioned during the period?

We took a steady,  conservative approach to managing the fund that paid off with
solid  returns.  We made few changes to the fund's  relatively  short  duration,
which was a benefit as bond prices declined overall during the period. (Duration
is a measure of portfolio  sensitivity to changes in interest rates. The shorter
a fund's duration,  the less dramatic  movements in its net asset value ought to
be when rates change.)

We tried to add value to the fund by  investing  the  majority  of its assets in
higher-yielding   securities,   such  as  corporate   debt  and   mortgage-  and
asset-backed  securities.   The  fund's  large  contingent  of  corporate  bonds
performed relatively well during the period and helped boost returns.

[bar graph - data below]

INTERMEDIATE-TERM BOND'S ONE-YEAR RETURNS SINCE INCEPTION
(Periods ended April 30)

       Intermediate-Term Bond      Lehman Intermediate Govt./Corp. Index

4/30/94*       -2.16%                             -2.32%
4/30/95         5.98%                              6.51%
4/30/96         7.57%                              7.84%
4/30/97         6.30%                              6.41%

This graph  illustrates the fund's returns since its inception and compares them
with the index's returns.  The fund's total returns include operating  expenses,
while the index's do not.  See page 36 for a definition  of the index.  * Return
from the fund's 3/1/94 inception date to 4/30/94.


12   Intermediate-Term Bond                         American Century Investments


                             INTERMEDIATE-TERM BOND

You also  maintained a sizable  portion of the fund's assets in corporate  bonds
rated BBB. Was that also to enhance the fund's yield?

Yes.  Corporate  securities  rated BBB tend to offer higher yields to compensate
for their greater credit risk. Adding BBB-rated  corporate  securities proved to
be a good way to enhance the fund's yield and boost returns. Nevertheless, we're
committed to maintaining the safety of investors'  principal,  so we worked very
closely  with  our  corporate  credit  research  team  to only  selectively  add
BBB-rated paper to the fund's portfolio.

The  credit  research  team plays an  integral  part in our  security  selection
process.  As a result,  we're often able to purchase securities that we feel are
undervalued  but are likely to  appreciate  in value  because  of credit  rating
upgrades.  The  trend  toward  improving  corporate  credit  resulted  in rating
upgrades and tighter spreads  between  corporate bonds rated AAA and BBB. Rating
upgrades benefit the fund because upgraded securities typically rise in value.

How has the  strong  growth of the U.S.  economy  affected  the  corporate  bond
market?

The big story in the corporate  bond market over the last several years has been
the  compression  of yield spreads  between  corporate and Treasury  securities.
Corporate bonds typically offer higher yields than Treasury debt as compensation
for increased  credit risk.  The  difference in yields is known as the "spread."
Spreads between  like-maturity  corporates and Treasurys have recently fallen to
ten-year  lows, or about  one-third of their  historical  averages.  Disciplined
fiscal management and a vibrant U.S. economy helped to improve corporate balance
sheets,  which  translated  into credit upgrades and higher prices for corporate
debt. The rapid pace of  stock-financed  corporate mergers and acquisitions also
improved  corporate  credit by  encouraging  economies of scale and  eliminating
inefficiencies.  Heavy demand from mutual fund managers and foreign  buyers also
helped increase prices and lower yields on corporate bonds.

Many analysts seem to think interest  rates are headed higher.  How would higher
rates affect the longer-maturity corporate securities the fund typically invests
in?

In general, the longer a fixed-income  security's  maturity,  the more its price
will  fluctuate  in response to a change in interest  rates.  That  explains why
short-  and  intermediate-term  securities  outperformed  longer-maturity  bonds
during the  period.  Dramatically  higher  rates  would  pose a greater  risk to
corporate bonds,  however. If the Fed were to increase interest rates sharply in
an effort to pre-empt  inflation,  higher  rates would  likely slow the economy.
Slower economic activity would hurt corporations'  balance sheets and reduce the
attractiveness of corporate debt.

[pie charts]

PORTFOLIO COMPOSITION BY SECURITY TYPE (as of 4/30/97)
Corporate Bonds 55%
U.S. Treasury Securities 20%
Mortgage-Backed Securities 9%
Asset-Backed Securities 7%
Cash 6%
Sovereign Governments &
Agencies 3%

PORTFOLIO COMPOSITION BY SECURITY TYPE (as of 10/31/96)
Corporate Bonds 52%
U.S. Treasury Securities 25%
Mortgage-Backed Securities 10%
Asset-Backed Securities 8%
Sovereign Governments &
Agencies 4%
Cash 1%


Semiannual Report                                    Intermediate-Term Bond   13


                             INTERMEDIATE-TERM BOND

What's your outlook for interest rates over the next six months?

We expect the U.S.  Federal  Reserve's  interest  rate policy  decisions  in the
coming months to hinge on two factors:  economic  growth and labor costs.  While
the current economic  expansion--now in its seventh year--is  remarkable for its
lack of  inflation,  we don't  think  the Fed  will  sit idly by if the  economy
continues to grow above trend. We think the economy will slow to a more moderate
pace in the coming months.  But if that doesn't happen, the Fed will likely feel
compelled to raise rates.

The Fed is concerned that rising labor costs will push inflation  higher.  Labor
costs are an important  consideration  for future inflation because they account
for  about   two-thirds  of  total  business   costs.   Improvements  in  worker
productivity  and  savings on health  care and  benefits  have so far kept labor
costs in check, but they may have run their course.

In addition, the unemployment rate fell to a 23-year low of 4.9% in April. Labor
market  capacity is  generally  defined as being tight at these  levels.  To the
extent that capacity is  stretched,  prices for labor will be pressured to rise.
Higher wages can be expected to boost consumer  spending,  which drives economic
growth. As a result,  we expect the Fed to continue to hike short-term  interest
rates  unless the economy  slows.  But because  interest  rates are already at a
level that should inhibit growth,  we don't think rates are headed  dramatically
higher.

With that outlook in mind, how will you manage the fund going forward?

We'll likely maintain the fund's  defensive  posture in the near term,  taking a
conservative  approach to managing its duration  and average  maturity.  We will
also continue to try to boost returns by purchasing  high-yielding securities at
what we feel are attractive values.

[pie charts]

PORTFOLIO COMPOSITION BY CREDIT RATING (as of 4/30/97)
AAA 42%
AA 6%
A 32%
BBB 20%

PORTFOLIO COMPOSITION BY CREDIT RATING (as of 10/31/96)
AAA 44%
AA 5%
A 32%
BBB 19%


14   Intermediate-Term Bond                         American Century Investments


                            SCHEDULE OF INVESTMENTS
                             INTERMEDIATE-TERM BOND

APRIL 30, 1997 (UNAUDITED)

Principal Amount                ($ in Thousands)                        Value
- --------------------------------------------------------------------------------

U. S. TREASURY SECURITIES
$      300    U. S. Treasury Notes, 6.125%,
                3/31/98                                            $   301
     1,050    U. S. Treasury Notes, 6.00%,
                9/30/98                                              1,048
       100    U. S. Treasury Notes, 7.75%,
                2/15/01                                                104
       200    U. S. Treasury Notes, 6.625%,
                3/31/02                                                201
       200    U. S. Treasury Notes, 5.75%,
                8/15/03                                                191
       200    U. S. Treasury Notes, 5.875%,
                2/15/04                                                191
       250    U. S. Treasury Notes, 7.25%,
                5/15/04                                                258
       250    U. S. Treasury Notes, 6.50%,
                8/15/05                                                246
       300    U. S. Treasury Notes, 5.875%,
                11/15/05                                               283
       100    U. S. Treasury Notes, 7.00%,
                7/15/06                                                102
       200    U. S. Treasury Notes, 6.25%,
                2/15/07                                                193
       225    U. S. Treasury Bonds, 7.625%,
                2/15/25                                                241
                                                                    ------
TOTAL U.S. TREASURY SECURITIES--19.5%                                3,359
                                                                    ------
   (Cost $3,395)

MORTGAGE-BACKED SECURITIES(1)
       730    FHLMC Pool #E00279, 6.50%,
                2/1/09                                                 715
       291    FNMA Pool #250627, 8.00%,
                7/1/26                                                 296
       486    GNMA Pool #002202,
                7.00%, 4/20/26                                         469
                                                                    ------
TOTAL MORTGAGE-BACKED
SECURITIES--8.6%                                                     1,480
                                                                    ------
   (Cost $1,490)

Principal Amount                ($ in Thousands)                        Value
- --------------------------------------------------------------------------------

ASSET-BACKED SECURITIES(1)
$      300    First Merchants Auto Receivables
                Corp., Series 1996-B, Class A2,
                6.80%, 5/15/01                                     $   302
       300    NationsBank Auto Owner Trust,
                Series 1996-A, Class B1, 6.75%,
                6/15/01                                                302
       300    UCFC Home Equity Loan, Series
                1996-B1, Class A2, 7.075%,
                4/15/10                                                302
       250    UCFC Home Equity Loan, Series
                1996-D1, Class A4, 6.776%,
                2/15/16                                                247
                                                                    ------
TOTAL ASSET-BACKED SECURITIES--6.7%                                  1,153
                                                                    ------
   (Cost $1,151)

CORPORATE BONDS
AUTOMOBILES & AUTO PARTS--1.9%
       300    General Motors Corp. Global Notes,
                9.625%, 12/1/00                                        326
                                                                    ------
BANKING--15.6%
       500    BankAmerica Corp., 7.75%,
                7/15/02                                                516
       300    Capital One Bank, 5.95%,
                2/15/01                                                287
       200    Chase Manhattan Corp., 8.80%,
                2/1/00                                                 200
       250    Corestates Capital Corp., 5.875%,
                10/15/03                                               233
       300    Deutsche Bank Financial, 6.70%,
                12/13/06                                               288
       300    MBNA Corp., 6.875%, 6/1/05                               290
       300    National Bank of Canada, Series B,
                8.125%, 8/15/04                                        315
       350    Santander Financial Issuances, Ltd.,
                7.00%, 4/1/06                                          343
       200    Wells Fargo & Co., 8.375%,
                5/15/02                                                212
                                                                    ------
                                                                     2,684
                                                                    ------

See Notes to Financial Statements


Semiannual Report                                    Intermediate-Term Bond   15


                            SCHEDULE OF INVESTMENTS
                             INTERMEDIATE-TERM BOND

APRIL 30, 1997 (UNAUDITED)

Principal Amount                ($ in Thousands)                        Value
- --------------------------------------------------------------------------------

COMMUNICATIONS SERVICES--2.6%
$      100    Tele-Communications, Inc., 8.25%,
                1/15/03                                            $   102
       350    Worldcom Inc., 7.75%, 4/1/07                             350
                                                                    ------
                                                                       452
                                                                    ------
DIVERSIFIED COMPANIES--1.7%
       300    Hanson Overseas BV, 6.75%,
                9/15/05                                                290
                                                                    ------
ENERGY--1.2%
       200    Texaco Capital Inc., 9.45%, 3/1/00                       214
                                                                    ------
FINANCIAL SERVICES--11.8%
       300    Comdisco, Inc., 6.375%, 11/30/01                         292
       100    Commercial Credit Co., 5.75%,
                7/1/00                                                  97
       200    Ford Motor Credit Co., 7.75%,
                10/1/99                                                205
       250    Ford Motor Credit Co., 6.75%,
                5/15/05                                                242
       300    Franchise Finance Corp., 7.00%,
                11/30/00                                               297
       250    Norwest Financial Inc., 6.25%,
                11/1/02                                                244
       300    Paine Webber Group Inc., MTN,
                7.96%, 4/28/00                                         309
       350    Wharf International Finance Ltd.,
                7.625%, 3/13/07 (Acquired
                3/6/97, Cost $347)(2)                                  344
                                                                    ------
                                                                     2,030
                                                                    ------
INSURANCE--4.0%
       300    Aetna Services Inc., 6.75%,
                8/15/01                                                298
       150    Delphi Financial Group, Inc., 9.31%,
                3/25/27                                                151
       250    Nationwide Mutual Insurance Co.,
                6.50%, 2/15/04 (Acquired
                2/9/96, Cost $252)(2)                                  239
                                                                    ------
                                                                       688
                                                                    ------
MEDIA & BROADCASTING--1.5%
       250    Time Warner Inc., 8.11%, 8/15/06                         255
                                                                    ------

Principal Amount                ($ in Thousands)                        Value
- --------------------------------------------------------------------------------

REAL ESTATE--3.8%
$      350    Price REIT, Inc. (The), 7.25%,
                11/1/00                                            $   350
       300    Spieker Properties Inc., 6.80%,
                12/15/01                                               296
                                                                    ------
                                                                       646
                                                                    ------
RETAIL (GENERAL MERCHANDISE)--3.9%
       300    Dayton Hudson Co., 9.25%,
                3/1/01                                                 320
       200    Sears, Roebuck & Co., Inc., MTN,
                8.29%, 6/10/02                                         211
       125    Sears, Roebuck & Co., Inc., MTN,
                8.23%, 10/21/04                                        133
                                                                    ------
                                                                       664
                                                                    ------
TOBACCO--3.5%
       250    Philip Morris Companies Inc.,
                6.80%, 12/1/03                                         243
       250    Philip Morris Companies Inc.,
                6.95%, 6/1/01                                          250
       100    RJR Nabisco, Inc., 8.75%,
                4/15/04                                                102
                                                                    ------
                                                                       595
                                                                    ------
UTILITIES--3.2%
       250    Idaho Power Co., 8.65%, 1/1/00                           262
       300    Pacific Gas & Electric Co., Series
                93C, 6.25%, 8/1/03                                     288
                                                                    ------
                                                                       550
                                                                    ------
TOTAL CORPORATE BONDS--54.7%                                         9,394
                                                                    ------
   (Cost $9,497)

OTHER CORPORATE DEBT--1.4%
       250    Nationsbank  Capital Trust III,  VRN,  
               6.366%,  7/15/97,  resets
               quarterly off the 3-month LIBOR 
               plus 0.55%, final maturity
               1/15/27                                                 243
                                                                    ------
   (Cost $245)

See Notes to Financial Statements


16   Intermediate-Term Bond                         American Century Investments


                            SCHEDULE OF INVESTMENTS
                             INTERMEDIATE-TERM BOND

APRIL 30, 1997 (UNAUDITED)

Principal Amount                ($ in Thousands)                        Value
- --------------------------------------------------------------------------------

SOVEREIGN GOVERNMENTS & AGENCIES
$      400    China Light & Power, 7.50%,
                4/15/06                                          $     401
       200    Hydro-Quebec, 7.375%, 2/1/03                             202
                                                                    ------
TOTAL SOVEREIGN GOVERNMENTS
& AGENCIES--3.5%                                                       603
                                                                    ------
   (Cost $603)

TEMPORARY CASH INVESTMENTS
    Repurchase Agreement, Goldman
      Sachs & Co., Inc. (U.S. Treasury
      obligations) in a joint trading
      account at 5.29%, dated
      4/30/97, due 5/1/97
      (Delivery value $100)                                            100
    Repurchase Agreement, J.P. Morgan
      Securities, Inc., (U.S. Treasury
      obligations) in a joint trading
      account at 5.375%, dated
      4/30/97, due 5/1/97
      (Delivery value $863)                                            863
                                                                    ------
TOTAL TEMPORARY CASH
INVESTMENTS--5.6%                                                      963
                                                                    ------
   (Cost $963)
TOTAL INVESTMENT SECURITIES--100.0%                                $17,195
                                                                   =======
   (Cost $17,344)

Notes to Schedule of Investments 
FHLMC = Federal Home Loan Mortgage  Corporation
FNMA = Federal National Mortgage Association 
GNMA = Government National Mortgage Association 
LIBOR = London Interbank Offered Rate 
MTN = Medium Term Note

resets = The frequency  with which a  fixed-income  security's  coupon  changes,
based on current market conditions or an underlying index. The more frequently a
security resets,  the less risk the investor is taking that the coupon will vary
significantly from current market rates.

VRN =  Variable  Rate  Note.  Interest  reset  date  is  indicated  and  used in
calculating the weighted  average  portfolio  maturity.  Rate shown is effective
April 30, 1997.

(1)  Final maturity indicated.  Expected remaining maturity used for purposes of
     calculating the weighted average portfolio maturity.

(2)  Security was purchased  under Rule 144A of the  Securities Act of 1933 and,
     unless registered under the Act or exempted from registration,  may only be
     sold  to  qualified  institutional   investors.   The  aggregate  value  of
     restricted  securities at April 30, 1997, was $583,062,  which  represented
     3.4% of the net assets of Intermediate-Term Bond.

See Notes to Financial Statements


Semiannual Report                                    Intermediate-Term Bond   17


<TABLE>
<CAPTION>
                                  BENHAM BOND

                                                                        AVERAGE ANNUAL RETURNS
                                            6 MONTHS       1 YEAR        3 YEARS       5 YEARS       10 YEARS
TOTAL RETURNS AS OF APRIL 30, 1997
<S>                                           <C>           <C>           <C>           <C>            <C>  
Benham Bond ...............................   1.45%         6.65%         7.39%         6.98%          8.04%
Lehman Aggregate Bond Index ...............   1.70%         7.08%         7.68%         7.36%          8.69%
Average A-Rated Corporate Debt Fund(1) ....   1.31%         6.46%         6.88%         7.12%          8.27%
Fund's Ranking Among
A-Rated Corporate Debt Funds(1) ...........    --       50 out of 122 26 out of 88  29 out of 51   18 out of 27

(1)  According to Lipper Analytical Services.
</TABLE>

See pages 36-37 for more information  about returns,  the comparative  index and
Lipper fund rankings.

[mountain graph - data below]

GROWTH OF $10,000 OVER TEN YEARS
Value on 4/30/97

Benham Bond                         $21,674
Lehman Aggregate Bond Index         $23,018

             Benham Bond      Lehman Aggregate Bond Index
Apr-87        $10,000                   $10,000
Jun-87        $10,043                   $10,098
Sep-87         $9,510                    $9,822
Dec-87        $10,220                   $10,393
Mar-88        $10,655                   $10,784
Jun-88        $10,710                   $10,911
Sep-88        $10,914                   $11,128
Dec-88        $11,073                   $11,213
Mar-89        $11,110                   $11,341
Jun-89        $12,122                   $12,244
Sep-89        $12,164                   $12,383
Dec-89        $12,621                   $12,843
Mar-90        $12,169                   $12,741
Jun-90        $12,617                   $13,206
Sep-90        $12,565                   $13,319
Dec-90        $13,383                   $13,993
Mar-91        $13,662                   $14,384
Jun-91        $13,815                   $14,620
Sep-91        $14,744                   $15,450
Dec-91        $15,725                   $16,233
Mar-92        $15,387                   $16,025
Jun-92        $16,024                   $16,673
Sep-92        $16,732                   $17,390
Dec-92        $16,605                   $17,437
Mar-93        $17,326                   $18,157
Jun-93        $17,773                   $18,638
Sep-93        $18,318                   $19,124
Dec-93        $18,289                   $19,136
Mar-94        $17,694                   $18,587
Jun-94        $17,404                   $18,395
Sep-94        $17,441                   $18,508
Dec-94        $17,469                   $18,578
Mar-95        $18,396                   $19,514
Jun-95        $19,699                   $20,703
Sep-95        $20,099                   $21,108
Dec-95        $21,013                   $22,008
Mar-96        $20,500                   $21,618
Jun-96        $20,537                   $21,741
Sep-96        $20,882                   $22,143
Dec-96        $21,523                   $22,808
Mar-97        $21,379                   $22,680
Apr-97        $21,674                   $23,018

Past  performance  does not  guarantee  future  results.  Investment  return and
principal  value will fluctuate,  and redemption  value may be more or less than
original cost.

The line representing the fund's total return includes  operating expenses (such
as transaction  costs and management fees) that reduce returns,  while the total
return line of the index does not.

PORTFOLIO AT A GLANCE
                            4/30/97   10/31/96
Number of Securities          45         46
Weighted Average Maturity 10.8 years 11.0 years
Average Duration           5.1 years  5.0 years
Expense Ratio               0.80%*      0.79%

* Annualized.

YIELD AS OF APRIL 30, 1997
                                       30-DAY
                                         SEC
                                        Yield

Benham Bond                             6.68%

Yield is defined in the Glossary on page 37.


18   Benham Bond                                    American Century Investments


                                  BENHAM BOND

Management Q & A

An interview with Bud Hoops, a senior portfolio  manager on the Diversified Bond
funds management team.

How did the fund perform?

The fund  outperformed  its peer group average during the six months ended April
30, 1997.  For the period,  the fund  returned  1.45%,  compared  with the 1.31%
average  return of the 122  "A-Rated  Corporate  Debt  Funds"  tracked by Lipper
Analytical Services. (See the Total Returns table on the previous page for other
fund performance comparisons.)

How was the fund positioned during the period?

We kept the fund's duration close to neutral, which was a benefit as bond prices
declined  overall  during  the  period.  (Duration  is a  measure  of  portfolio
sensitivity  to changes in interest  rates.  The shorter the duration,  the less
dramatic  movements  in a fund's net asset value tend to be when rates  change.)
Rather  than try to guess the  direction  of interest  rates,  we took a steady,
conservative  approach  to  managing  the fund that paid off with  above-average
returns.

We also enhanced the fund's  returns by purchasing  securities  with  relatively
high yields,  such as corporate debt and mortgage- and asset-backed  

[bar graph - data below]

BENHAM BOND'S ONE-YEAR RETURNS FOR THE PAST TEN YEARS (Periods ended April 30)

             Benham Bond       Lehman Aggregate Bond Index

4/30/88         5.98%                     7.26%
4/30/89         6.96%                     7.94%
4/30/90         5.38%                     9.03%
4/30/91        15.59%                    15.19%
4/30/92        12.04%                    11.00%
4/30/93        12.84%                    13.26%
4/30/94         0.26%                     0.85%
4/30/95         6.62%                     7.31%
4/30/96         8.92%                     8.64%
4/30/97         6.65%                     7.08%

This graph  illustrates  the fund's  returns over the past 10 years and compares
them with the  index's  returns.  The fund's  total  returns  include  operating
expenses, while the index's do not. See page 36 for a definition of the index.


Semiannual Report                                               Benham Bond   19


                                  BENHAM BOND

securities.  We maintained the fund's  holdings of  mortgage-backed  securities,
which were the  top-performing  fixed-income  sector over the past year. We also
increased the fund's holdings of corporate securities, which performed well.

You maintained about 20% of the fund's assets in corporate bonds rated BBB. Why?

Selectively  adding  corporate  securities  rated BBB proved to be a good way to
enhance the fund's  yield and boost  returns.  We worked very  closely  with our
corporate  credit research team to identify  securities we felt were undervalued
by virtue of their credit rating or market valuation. The trend toward improving
corporate  credit  resulted  in rating  upgrades  and  tighter  spreads  between
corporate  bonds rated AAA and BBB.  (The  "spread" is the  difference  in yield
between  different types or grades of securities.)  Rating upgrades  benefit the
fund because upgraded securities typically rise in value.

What's behind the trend toward corporate credit upgrades?

Disciplined  fiscal  management  and a vibrant  U.S.  economy  helped to improve
corporate  balance  sheets,  which  translated  into credit  upgrades and higher
prices for corporate debt. The rapid pace of  stock-financed  corporate  mergers
and  acquisitions  also improved  corporate  credit by encouraging  economies of
scale and eliminating inefficiencies. Heavy demand from mutual fund managers and
foreign buyers also helped increase prices and lower yields on corporate bonds.

What's the attraction of holding foreign government and agency securities?

We consistently maintained about 5% of the fund in foreign government and agency
securities as a defensive play. Because their issuers are international, holding
foreign  securities  is a good way to enhance  the fund's  diversification.  For
example,  if the U.S.  Federal Reserve were to raise interest rates further,  it
would likely have an adverse effect on U.S. fixed-income  securities.  Corporate
debt in particular would be vulnerable to higher rates because the economy would
likely slow.  Slower economic activity would hurt  corporations'  balance sheets
and reduce the  attractiveness of their debt securities.  Foreign government and
agency  securities  aren't as closely tied to the U.S.  economy,  so they should
hold up relatively well if the Fed continues to raise rates.

You added a new type of corporate  security  called  capital  notes to the fund.
What are capital notes?

Capital notes, also known as trust-preferred  securities, are hybrid debt-equity
securities.  Banks  have  been the  biggest  issuers  of  capital  notes.  These
securities are created


[pie charts]

PORTFOLIO COMPOSITION BY SECURITY TYPE (as of 4/30/97)
Corporate Bonds 61%
Mortgage-Backed Securities 14%
U.S. Treasury Securities 11%
Asset-Backed Securities 6%
Sovereign Governments &
Agencies 5%
Other 3%

PORTFOLIO COMPOSITION BY SECURITY TYPE (as of 10/31/96)
Corporate Bonds 56%
U.S. Treasury Securities 24%
Mortgage-Backed Securities 14%
Sovereign Governments &
Agencies 5%
U.S. Government Agency
Securities 1%

20   Benham Bond                                    American Century Investments


                                  BENHAM BOND

when a company issues debt to a trust,  which then issues preferred  securities.
Corporations  like to issue  this type of debt  because  it's a cheap  source of
capital with  tax-deductible  interest  payments.  Investors  like capital notes
because they  typically  offer  attractive  yields with  relatively  high credit
quality. However, the government is soon expected to close the tax loophole that
allows companies to issue this type of security.

You've talked a lot about corporate credit  considerations.  How does the credit
research team fit into the overall management of the fund?

The  credit  research  team plays an  integral  part in our  security  selection
process, reviewing every security considered for purchase by our corporate money
market and bond funds. As a result, we're often able to purchase securities that
we feel are  undervalued but are likely to appreciate in value because of credit
rating upgrades.

What's your outlook for interest rates over the next six months?

We expect the U.S.  Federal  Reserve's  interest  rate policy  decisions  in the
coming months to hinge on two factors:  economic  growth and labor costs.  While
the current economic  expansion--now in its seventh year--is  remarkable for its
lack of  inflation,  we don't  think  the Fed  will  sit idly by if the  economy
continues to grow above trend. We think the economy will slow to a more moderate
pace in the coming months.  But if that doesn't happen, the Fed will likely feel
compelled to raise rates.

The Fed is concerned that rising labor costs will push inflation  higher.  Labor
costs are an important  consideration  for future inflation because they account
for  about   two-thirds  of  total  business   costs.   Improvements  in  worker
productivity  and  savings on health  care and  benefits  have so far kept labor
costs in check, but they may have run their course.

In addition, the unemployment rate fell to a 23-year low of 4.9% in April. Labor
market  capacity is  generally  defined as being tight at these  levels.  To the
extent that capacity is  stretched,  prices for labor will be pressured to rise.
Higher wages can be expected to boost consumer  spending,  which drives economic
growth. As a result,  we expect the Fed to continue to hike short-term  interest
rates  unless the economy  slows.  But because  interest  rates are already at a
level that should inhibit growth,  we don't think rates are headed  dramatically
higher.

With that outlook in mind, how will you manage the fund going forward?

We'll likely maintain the fund's  defensive  posture in the near term,  taking a
conservative  approach to managing its duration  and average  maturity.  We will
also continue to try to boost returns by purchasing  high-yielding securities at
what we feel are attractive values.

[pie charts]

PORTFOLIO COMPOSITION BY CREDIT RATING (as of 4/30/97)
AAA 36%
AA 5%
A 37%
BBB 22%

PORTFOLIO COMPOSITION BY CREDIT RATING (as of 10/31/96)
AAA 43%
AA 7%
A 29%
BBB 21%


Semiannual Report                                               Benham Bond   21


                            SCHEDULE OF INVESTMENTS
                                  BENHAM BOND

APRIL 30, 1997 (UNAUDITED)

Principal Amount                ($ in Thousands)                        Value
- --------------------------------------------------------------------------------

U.S. TREASURY SECURITIES
$    4,000    U.S. Treasury Notes, 5.75%,
                9/30/97                                          $   4,003
     2,000    U.S. Treasury Notes, 5.625%,
                10/31/97                                             1,999
     1,500    U.S. Treasury Notes, 5.875%,
                1/31/99                                              1,492
     6,000    U.S. Treasury Notes, 5.50%,
                12/31/00                                             5,803
                                                                    ------
TOTAL U.S. TREASURY SECURITIES--10.5%                               13,297
                                                                    ------
   (Cost $13,521)

U.S. GOVERNMENT AGENCY SECURITIES--1.4%
     2,000    Tennesse Valley Authority, 6.875%,
                12/15/43                                             1,793
                                                                    ------
   (Cost $1,854)

MORTGAGE-BACKED SECURITIES(1)
       825    FHLMC REMIC, Series 19, Class
                E PAC, 8.00%, 8/15/19                                  835
       997    FHLMC REMIC, Series 116, Class
                F PAC, 8.50%, 2/15/20                                1,024
     1,068    FNMA REMIC, Series 1989-35,
                Class G, 9.50%, 7/25/19                              1,140
       716    FNMA REMIC, Series 1990-88,
                Class H PAC, 7.75%, 9/25/19                            720
       932    FNMA REMIC, Series 1991-21,
                Class G PAC, 6.00%, 12/25/19                           927
     4,744    FNMA Pool #250452, 6.50%,
                1/1/26                                               4,491
     5,277    GNMA Pool #313107, 7.00%,
                11/15/22                                             5,147
     3,929    GNMA Pool #423865, 8.00%,
                6/15/26                                              3,993
                                                                    ------
TOTAL MORTGAGE-BACKED
SECURITIES--14.5%                                                   18,277
                                                                    ------
   (Cost $18,089)

Principal Amount                ($ in Thousands)                        Value
- --------------------------------------------------------------------------------

ASSET-BACKED SECURITIES(1)
$    3,000    The Money Store Home Equity
                Trust, Series 1996-D, Class A3,
                6.295%, 11/15/11                                  $  2,989
     5,000    UCFC Home Equity Loan, Series
                1995-D1, Class A2, 6.20%,
                3/10/14                                              4,983
                                                                    ------
TOTAL ASSET-BACKED SECURITIES--6.3%                                  7,972
                                                                    ------
   (Cost $7,966)

CORPORATE BONDS
AEROSPACE & DEFENSE--3.2%
     2,000    Boeing Co., 7.875%, 4/15/43                            2,072
     2,000    Lockheed Martin Corp., 7.25%,
                5/15/06                                              2,005
                                                                    ------
                                                                     4,077
                                                                    ------
AIRLINES--4.4%
     3,355    Delta Air Lines Inc., Equipment
                Trust Certificates, 7.541%,
                10/11/11                                             3,288
     2,000    United Air Lines, 10.67%, 5/1/04                       2,323
                                                                    ------
                                                                     5,611
                                                                    ------
BANKING--16.5%
     5,000    Citicorp Euro, 7.00%, 1/2/04                           4,962
     2,000    Corestates Capital Corp., 5.875%,
                10/15/03                                             1,865
     3,000    First Union Corp., 8.77%,
                11/15/04,                                            3,131
      5,000   National Bank of Canada, 8.125%,
                8/15/04                                              5,244
     2,000    Nationsbank Capital Trust II, 7.83%,
                12/15/26                                             1,930
      2,000   Santander Financial Issuances Ltd.,
                6.375%, 2/15/11                                      1,800
     2,000    Wells Fargo Capital, 7.96%,
                12/15/26                                             1,947
                                                                    ------
                                                                    20,879
                                                                    ------
CHEMICALS & RESINS--4.9%
     5,000    ARCO Chemical Co., 10.25%,
                11/1/10                                              6,244
                                                                    ------

See Notes to Financial Statements


22   Benham Bond                                    American Century Investments


                            SCHEDULE OF INVESTMENTS
                                  BENHAM BOND

APRIL 30, 1997 (UNAUDITED)

Principal Amount                ($ in Thousands)                        Value
- --------------------------------------------------------------------------------

COMMUNICATIONS SERVICES--1.6%
$    2,000    Worldcom Inc., 7.75%, 4/1/07                        $  1,997
                                                                    ------
COMPUTER SYSTEMS--1.1%
     1,500    International Business Machines
                Corp., 7.125%, 12/1/96                               1,387
                                                                    ------
ENERGY--2.3%
     3,000    Columbia Gas Systems, 7.42%,
                11/28/15                                             2,876
                                                                    ------
FINANCIAL SERVICES--6.8%
     4,000    Lehman Brothers Holdings Inc.,
                6.625%, 11/15/00                                     3,960
     3,000    Paine Webber Group Inc., MTN,
                7.96%, 4/28/00                                       3,086
     1,500    Wharf International Finance Ltd.,
                7.625%, 3/13/07 (Acquired
                3/6/97, Cost $1,488)(2)                              1,476
                                                                    ------
                                                                     8,522
                                                                    ------
INSURANCE--3.4%
     1,000    Delphi Financial Group, Inc., 9.31%,
                3/25/27                                              1,009
     3,000    Lincoln National Corp., 9.125%,
                10/1/24                                              3,319
                                                                    ------
                                                                     4,328
                                                                    ------
MEDIA & BROADCAST--3.8%
     3,000    News America Holdings, 7.60%,
                10/11/15                                             2,831
     2,000    Time Warner Inc., 6.85%, 1/15/26                       1,965
                                                                    ------
                                                                     4,796
                                                                    ------
REAL ESTATE--3.5%
     1,350    Price REIT, Inc. (The), 7.25%,
                11/1/00                                              1,348
     3,000    Spieker Properties Inc., MTN,
                7.58%, 12/17/01                                      3,053
                                                                    ------
                                                                     4,401
                                                                    ------
TOBACCO--2.3%
     3,000    Philip Morris Companies Inc.,
                6.80%, 12/1/03                                       2,918
                                                                    ------

Principal Amount                ($ in Thousands)                        Value
- --------------------------------------------------------------------------------

UTILITIES--7.1%
$    5,000    Pacific Gas & Electric Co., 5.50%,
                6/1/99                                          $    4,888
     4,000    Union Electric Co., 7.65%,
                7/15/03                                              4,135
                                                                    ------
                                                                     9,023
                                                                    ------
TOTAL CORPORATE BONDS--60.9%                                        77,059
                                                                    ------
   (Cost $77,029)

SOVEREIGN GOVERNMENTS & AGENCIES
     3,000    Korea Electric Power, 6.375%,
                12/1/03                                              2,888
     4,000    Province of Quebec Bonds,
                7.125%, 2/9/24                                       3,695
                                                                    ------
TOTAL SOVEREIGN GOVERNMENTS
& AGENCIES--5.2%                                                     6,583
                                                                    ------
   (Cost $6,687)

TEMPORARY CASH INVESTMENTS--1.2%
   Repurchase Agreement, J.P. Morgan Securities,
      Inc., (U.S. Treasury obligations), in a joint
      trading account at 5.375%, dated 4/30/97,
      due 5/1/97 (Delivery value $1,480)                             1,480
                                                                    ------
   (Cost $1,480)
TOTAL INVESTMENT SECURITIES--100.0%                               $126,461
                                                                  ========
   (Cost $126,626)

Notes to Schedule of Investments
FHLMC = Federal Home Loan Mortgage Corporation
FNMA = Federal National Mortgage Association
GNMA = Government National Mortgage Association
MTN = Medium Term Note

(1)  Final maturity indicated.  Expected remaining maturity used for purposes of
     calculating the weighted average portfolio maturity.

(2)  Security was purchased  under Rule 144A of the  Securities Act of 1933 and,
     unless registered under the Act or exempted from registration,  may only be
     sold  to  qualified  institutional   investors.   The  aggregate  value  of
     restricted  securities at April 30, 1997, was $1,476,000 which  represented
     1.2% of the net assets of the Benham Bond Fund.

See Notes to Financial Statements


Semiannual Report                                               Benham Bond   23


<TABLE>
<CAPTION>
                      STATEMENTS OF ASSETS AND LIABILITIES

                                                                 LIMITED-TERM     INTERMEDIATE-TERM      BENHAM
                                                                     BOND                BOND              BOND

                                                            ($ and Shares in Thousands Except Per Share Amounts)
APRIL 30, 1997 (UNAUDITED)

ASSETS
<S>                                                                      <C>             <C>            <C>  
Investment securities, at value (identified cost of $9,270,
  $17,344 and $126,626, respectively) (Note 3) ....................  $9,271          $17,195         $126,461
Cash ..............................................................      --               --               79
Receivable for capital shares sold ................................      --                3               11
Receivable for investments sold ...................................       3               --               40
Interest receivable ...............................................      99              249            2,244
                                                                      -----           ------          -------
                                                                      9,373           17,447          128,835
                                                                      -----           ------          -------


LIABILITIES
Disbursements in excess of demand deposit cash ....................      58              142              248
Payable for capital shares redeemed ...............................       1                4              218
Dividends payable .................................................       7               14              112
Accrued management fees (Note 2) ..................................       5               11               84
                                                                      -----           ------          -------
                                                                         71              171              662
                                                                      -----           ------          -------
Net Assets Applicable to Outstanding Shares .......................  $9,302          $17,276         $128,173
                                                                     ======          =======         ========

CAPITAL SHARES, $0.01 PAR VALUE
Authorized ........................................................ 100,000          100,000          100,000
                                                                    =======          =======          =======
Outstanding .......................................................     942            1,768           13,661
                                                                    =======          =======          =======
Net Asset Value Per Share .........................................   $9.87            $9.77            $9.38
                                                                    =======          =======          =======

NET ASSETS CONSIST OF:
Capital (par value and paid in surplus) ...........................  $9,296          $17,439         $128,467
Accumulated undistributed net realized gain (loss)
  from investment transactions ....................................       5              (14)            (129)
Net unrealized appreciation (depreciation)
  on investments (Note 3) .........................................       1             (149)            (165)
                                                                     ------          -------         --------
                                                                     $9,302          $17,276         $128,173
                                                                    =======          =======          =======

</TABLE>

See Notes to Financial Statements

24   Statements of Assets and Liabilities           American Century Investments


<TABLE>
<CAPTION>
                            STATEMENTS OF OPERATIONS

                                                                 LIMITED-TERM     INTERMEDIATE-TERM      BENHAM
                                                                     BOND                BOND              BOND

                                                                                   ($ in Thousands)
For the Six Months Ended APRIL 30, 1997 (Unaudited)

INVESTMENT INCOME
Income:
<S>                                                                    <C>              <C>           <C>   
Interest ......................................................        $256             $553          $4,739
                                                                      -----            -----          ------

Expenses:
Management fees (Note 2) ......................................          28               61             536
Directors' fees and expenses ..................................          --               --               1
                                                                      -----            -----          ------
 ..............................................................          28               61             537
                                                                      -----            -----          ------
Net investment income .........................................         228              492           4,202
                                                                      -----            -----          ------

REALIZED AND UNREALIZED GAIN (LOSS)
ON INVESTMENTS (NOTE 3)
Net realized gain (loss) on investments .......................           3               (9)           (123)
Change in net unrealized appreciation
  (depreciation) on investments ...............................         (51)            (225)         (2,162)
                                                                      -----            -----          ------

Net realized and unrealized
loss on investments ...........................................         (48)            (234)         (2,285)
                                                                      -----            -----          ------

Net Increase in Net Assets
Resulting from Operations .....................................        $180             $258          $1,917
                                                                       ====             ====          ======
</TABLE>


See Notes to Financial Statements

Semiannual Report                                  Statements of Operations   25

<TABLE>
<CAPTION>
                      STATEMENTS OF CHANGES IN NET ASSETS

Six Months Ended APRIL 30, 1997 
(Unaudited) AND YEAR ENDED 
OCTOBER 31, 1996
                                             LIMITED-TERM           INTERMEDIATE-TERM             BENHAM
                                                 BOND                      BOND                     BOND

Increase (Decrease) in Net Assets         1997        1996         1997         1996        1997         1996
OPERATIONS                                                     ($ and Shares in Thousands)

<S>                                     <C>         <C>        <C>          <C>         <C>         <C>       
Net investment income ................. $   228     $   432    $     492    $     874   $    4,202  $    9,024
Net realized gain (loss)
  on investments ......................       3          13           (9)          (4)        (123)      1,341
Change in net unrealized appreciation
  (depreciation) on investments .......     (51)        (31)        (225)        (131)      (2,162)     (3,546)
                                          -----         ---        -----        -----      -------      ------ 
Net increase in net assets
  resulting from operations ...........     180         414          258          739        1,917       6,819
                                          -----         ---        -----        -----      -------      ------ 

DISTRIBUTIONS TO SHAREHOLDERS
From net investment income ............    (228)       (432)        (492)        (874)      (4,202)     (9,024)
From net realized gains
  from investment transactions ........      --          --           --         (132)      (1,310)       (228)
                                          -----         ---        -----        -----      -------      ------ 
Decrease in net assets
  from distributions ..................    (228)       (432)        (492)      (1,006)      (5,512)     (9,252)
                                          -----         ---        -----        -----      -------      ------ 

CAPITAL SHARE TRANSACTIONS
Proceeds from shares sold .............   6,115       2,982        9,678        9,981       27,399      63,329
Proceeds from reinvestment
  of distributions ....................     215         413          432          895        5,145       8,559
Payments for shares redeemed ..........  (5,072)     (2,478)      (8,226)      (7,810)     (43,343)    (76,111)
                                          -----       -----        -----        -----      -------      ------ 
Net increase (decrease) in net assets
  from capital share transactions .....   1,258         917        1,884        3,066      (10,799)     (4,223)
                                          -----         ---        -----        -----      -------      ------ 
Net increase (decrease)
  in net assets .......................   1,210         899        1,650        2,799      (14,394)     (6,656)

NET ASSETS
Beginning of period ...................   8,092       7,193       15,626       12,827      142,567     149,223
                                          -----       -----        -----        -----      -------      ------ 

End of period .........................  $9,302      $8,092      $17,276      $15,626     $128,173    $142,567
                                         ======      ======      =======      =======     ========    ========

TRANSACTIONS IN SHARES OF THE FUNDS
Sold ..................................     618         300          982        1,005        2,880       6,596
Issued in reinvestment of
  distributions .......................      21          42           44           90          542         891
Redeemed ..............................    (512)       (249)        (835)        (792)      (4,562)     (7,937)
                                          -----         ---        -----        -----      -------      ------ 
Net increase (decrease) ...............     127          93          191          303       (1,140)       (450)
                                         ======      ======      =======      =======     ========    ========

</TABLE>

See Notes to Financial Statements


26   Statements of Changes in Net Assets            American Century Investments


                         NOTES TO FINANCIAL STATEMENTS

APRIL 30, 1997 (UNAUDITED)

1. Organization and Summary of Significant Accounting Policies

Organization--American   Century  Mutual  Funds,   Inc.  (the   Corporation)  is
registered under the Investment  Company Act of 1940 as an open-end  diversified
management investment company.  American Century - Benham Limited-Term Bond Fund
(Limited-Term),   American   Century  -  Benham   Intermediate-Term   Bond  Fund
(Intermediate-Term),  and American Century - Benham Bond Fund (Benham Bond) (the
Funds)  are  three  of  the  seventeen  funds  issued  by the  Corporation.  The
investment  objective of  Limited-Term  is to seek  income.  The Fund intends to
pursue this by investing in bonds and other debt  obligations  and maintaining a
weighted  average  maturity of five years or less. The  investment  objective of
Intermediate-Term  is to seek a competitive level of income. The Fund intends to
pursue this by investing in bonds and other debt  obligations  and maintaining a
weighted  average  maturity of three to ten years.  The investment  objective of
Benham Bond is to seek a high level of income.  The Fund  intends to pursue this
by  investing in bonds and other debt  obligations  and  maintaining  a weighted
average  maturity  of ten years or  greater.  On  September  3, 1996,  the Funds
implemented a multiple class structure whereby the Funds are authorized to issue
two classes of shares: the Investor Class and the Advisor Class.

The shares  outstanding  prior to September 3, 1996, were designated as Investor
Class shares.  The two classes of shares differ  principally in their respective
shareholder servicing and distribution expenses and arrangements.  All shares of
each Fund  represent  an equal pro rata  interest  in the assets of the class to
which such shares belong, and have identical voting,  dividend,  liquidation and
other  rights  and the same  terms and  conditions,  except  for class  specific
expenses  and  exclusive  rights to vote on matters  affecting  only  individual
classes.  Sale of the Advisor class had not commenced as of the report date. The
following significant accounting policies,  related to all classes of the Funds,
are in accordance with accounting  policies generally accepted in the investment
company industry.

Security Valuations--  Securities are valued through valuations obtained through
a  commercial  pricing  service or at the mean of the most  recent bid and asked
prices. When valuations are not readily available, securities are valued at fair
value as  determined  in  accordance  with  procedures  adopted  by the Board of
Directors.

Security  Transactions--Security  transactions  are  accounted  for on the  date
purchased  or  sold.  Net  realized  gains  and  losses  are  determined  on the
identified cost basis, which is also used for federal income tax purposes.

Investment Income--Interest income is recorded on the accrual basis and includes
amortization of discounts and premiums.

Repurchase  Agreements--The  Funds may enter  into  repurchase  agreements  with
institutions that the Funds'  investment  manager,  American Century  Investment
Management,  Inc. (ACIM),  has determined are creditworthy  pursuant to criteria
adopted by the Board of  Directors.  Each  repurchase  agreement  is recorded at
cost.  The  Funds  require  that  the  securities   purchased  in  a  repurchase
transaction be transferred to the custodian in a manner sufficient to enable the
Funds to obtain those  securities in the event of a default under the repurchase
agreement.  ACIM  monitors,  on a  daily  basis,  the  value  of the  securities
transferred  to ensure that the value,  including  interest,  of the  securities
under each repurchase  agreement is equal to or greater than amounts owed to the
Funds under each repurchase agreement.

Joint Trading  Account--Pursuant  to an Exemptive Order issued by the Securities
and  Exchange  Commission,  the Funds,  along with other  registered  investment
companies  having   management   agreements  with  ACIM  and  Benham  Management
Corporation, may transfer uninvested cash balances into a joint trading account.
These  balances  are  invested  in one or more  repurchase  agreements  that are
collateralized by U.S. Treasury or Agency obligations.

Income Tax  Status--It is the Funds' policy to distribute all taxable income and
capital gains to shareholders and to otherwise qualify as a regulated investment
company under provisions of the Internal Revenue Code. Accordingly, no provision
has been made for federal income taxes.

Distributions  to  Shareholders--Distributions  from net  investment  income are
declared daily and distributed  monthly.  Distributions  from net realized gains
are declared and paid annually.

The character of distributions  made during the year from net investment  income
or net  realized  gains may differ  from  their  ultimate  characterization  for
federal income tax purposes.  These differences are primarily due to differences
in the  recognition of income and expense items for financial  statement and tax
purposes.

Supplementary Information--Certain officers and directors of the Corporation are
also officers  and/or  directors,  and as a group,  controlling  stockholders of
American Century  Companies,  Inc., the parent of the  Corporation's  investment
manager,  ACIM,  the  Corporation's  distributor,  American  Century  Investment
Services,  Inc. and the Corporation's  transfer agent, American Century Services
Corporation.


Semiannual Report                             Notes to Financial Statements   27


                         NOTES TO FINANCIAL STATEMENTS

APRIL 30, 1997 (UNAUDITED)

Use of  Estimates--The  preparation of financial  statements in conformity  with
generally accepted  accounting  principles requires management to make estimates
and assumptions  that affect the reported  amounts of assets and liabilities and
disclosure of  contingent  assets and  liabilities  at the date of the financial
statements  and the reported  amounts of increases  and  decreases in net assets
from  operations  during the  period.  Actual  results  could  differ from these
estimates.

- --------------------------------------------------------------------------------
2. Transactions with Related Parties

The Corporation  has entered into Management  Agreements with ACIM that provides
each Fund with  investment  advisory and  management  services in exchange for a
single,  unified  management  fee per class.  The  Agreements  provide  that all
expenses of the Funds, except brokerage commissions,  taxes, interest,  expenses
of those directors who are not considered "interested persons" as defined in the
Investment  Company  Act of 1940  (including  counsel  fees)  and  extraordinary
expenses, will by paid by ACIM. The fee is computed daily and paid monthly based
on each Fund's average closing net assets during the previous month.  The annual
management fee for the Investor Class of  Limited-Term,  Intermediate-Term,  and
Benham Bond is 0.70%, 0.75% and 0.80%, respectively.

- --------------------------------------------------------------------------------
3. Investment Transactions

Investment  transactions  (excluding short-term  investments) for the six months
ended April 30, 1997, were as follows:

<TABLE>
                                                                                                        BENHAM
                                                               LIMITED-TERM     INTERMEDIATE-TERM        BOND
PURCHASES                                                                        ($ in Thousands)

<S>                                                               <C>                <C>               <C>    
U. S. Treasury & Agency Obligations ..........................    $2,291             $3,611            $11,491
Other Debt Obligations .......................................     1,810              3,514             23,732

PROCEEDS FROM SALES

U. S. Treasury & Agency Obligations ..........................    $2,181             $4,125            $31,782
Other Debt Obligations .......................................       997              2,090             14,155

On April 30, 1997, the composition of unrealized appreciation  (depreciation) of
investment  securities  based on the aggregate cost of  investments  for federal
income tax purposes was as follows:

                                                                                                        BENHAM
                                                               LIMITED-TERM     INTERMEDIATE-TERM        BOND
                                                                                ($ in Thousands)
Appreciation .................................................    $    17           $    49           $  1,392
(Depreciation) ...............................................       (16)              (198)            (1,557)
Net ..........................................................         1               (149)              (165)
</TABLE>

The aggregate cost of  investments  for federal income tax purposes was the same
as the cost for financial reporting purposes.


28   Notes to Financial Statements                  American Century Investments


                         NOTES TO FINANCIAL STATEMENTS

APRIL 30, 1997 (UNAUDITED)

- --------------------------------------------------------------------------------
4. Corporate Events
<TABLE>
The following name changes became effective January 1, 1997:

                  NEW NAMES                                              FORMER NAMES
<S>              <C>                                                     <C>  
Funds' Issuer:    American Century Mutual Funds, Inc.                    Twentieth Century Investors, Inc.
Funds:            American Century - Benham Limited-Term Bond Fund       Limited-Term Bond
                  American Century - Benham Intermediate-Term Bond Fund  Intermediate-Term Bond
                  American Century - Benham Bond Fund                    Long-Term Bond
Parent Company:   American Century Companies, Inc.                       Twentieth Century Companies, Inc.
Distributor:      American Century Investment Services, Inc.             Twentieth Century Securities, Inc.
Transfer Agent:   American Century Services Corporation                  Twentieth Century Services, Inc.
</TABLE>


Semiannual Report                             Notes to Financial Statements   29

<TABLE>
<CAPTION>
                              FINANCIAL HIGHLIGHTS
                               LIMITED-TERM BOND

 For a Share Outstanding Throughout the Years Ended October 31 (except as noted)

                                                                1997(1)       1996         1995         1994(2)

PER-SHARE DATA
Net Asset Value,
<S>                                                              <C>          <C>          <C>         <C>   
Beginning of Period ..........................................   $9.93        $9.96        $9.68       $10.00
                                                                 -----        -----        -----       ------
Income From Investment Operations
  Net Investment Income ......................................    0.28         0.56         0.56         0.31
  Net Realized and Unrealized Gain (Loss)
  on Investment Transactions .................................   (0.06)       (0.03)        0.28        (0.32)
                                                                 -----        -----        -----       ------
  Total From Investment Operations ...........................    0.22         0.53         0.84        (0.01)
                                                                 -----        -----        -----       ------
Distributions
  From Net Investment Income .................................   (0.28)       (0.56)       (0.56)       (0.31)
                                                                 -----        -----        -----       ------
Net Asset Value, End of Period ...............................   $9.87        $9.93        $9.96        $9.68
                                                                 =====        =====        =====        =====
   Total Return(3) ...........................................    2.20%        5.48%        8.89%       (0.08%)

RATIOS/SUPPLEMENTAL DATA
Ratio of Operating Expenses
to Average Net Assets ........................................  0.69%(4)       0.68%        0.69%      0.70%(4)
Ratio of Net Investment Income
to Average Net Assets ........................................  5.63%(4)       5.63%        5.70%      4.79%(4)
Portfolio Turnover Rate ......................................      44%         121%         116%          48%
Net Assets, End
of Period (in thousands) .....................................   $9,302      $8,092       $7,193        $4,375

(1)  Six months ended April 30, 1997 (unaudited).
(2)  March 1, 1994 (inception) through October 31, 1994.
(3)  Total return assumes reinvestment of dividends and capital gains 
     distributions, if any. Total returns for periods less than one year are
     not annualized.
(4)  Annualized.
</TABLE>

See Notes to Financial Statements


30   Financial Highlights                           American Century Investments


<TABLE>
<CAPTION>
                              FINANCIAL HIGHLIGHTS
                             INTERMEDIATE-TERM BOND

                                                                1997(1)       1996         1995         1994(2)

PER-SHARE DATA
Net Asset Value,
<S>                                                              <C>         <C>           <C>         <C>   
Beginning of Period ........................................     $9.91       $10.07        $9.53       $10.00
                                                                 -----        -----        -----       ------
Income From Investment Operations
  Net Investment Income ....................................      0.29         0.58         0.59         0.34
  Net Realized and Unrealized Gain (Loss)
  on Investment Transactions ...............................     (0.14)       (0.06)        0.54        (0.47)
                                                                 -----        -----        -----       ------
  Total From Investment Operations .........................      0.15         0.52         1.13        (0.13)
                                                                 -----        -----        -----       ------
Distributions
  From Net Investment Income ...............................     (0.29)       (0.58)       (0.59)       (0.34)
  From Net Realized Gains on
  Investment Transactions ..................................     --           (0.10)       --           --
                                                                 -----        -----        -----       ------
  Total Distributions ......................................     (0.29)       (0.68)       (0.59)       (0.34)
                                                                 -----        -----        -----       ------
Net Asset Value, End of Period .............................     $9.77        $9.91       $10.07        $9.53
                                                                 =====        =====       ======        =====
  Total Return(3) ..........................................      1.57%        5.36%       12.19%       (1.24%)

RATIOS/SUPPLEMENTAL DATA
Ratio of Operating Expenses
to Average Net Assets ......................................    0.75%(4)       0.74%       0.74%       0.75%(4)
Ratio of Net Investment Income
to Average Net Assets ......................................    6.02%(4)       5.90%       6.05%       5.23%(4)
Portfolio Turnover Rate ....................................        39%          87%        133%           48%
Net Assets, End of
Period (in thousands) ......................................    $17,276     $15,626     $12,827        $4,262

(1)  Six months ended April 30, 1997 (unaudited).
(2)  March 1, 1994 (inception) through October 31, 1994.
(3)  Total return assumes reinvestment of dividends and capital gains
     distributions, if any. Total returns for periods less than one year are
     not annualized.
(4)  Annualized.
</TABLE>

See Notes to Financial Statements


Semiannual Report                                      Financial Highlights   31

<TABLE>
<CAPTION>
                              FINANCIAL HIGHLIGHTS
                                  BENHAM BOND

 For a Share Outstanding Throughout the Years Ended October 31 (except as noted)

                                      1997(1)       1996         1995         1994        1993(2)       1992(2)

PER-SHARE DATA
Net Asset Value,
<S>                                   <C>           <C>          <C>         <C>           <C>          <C>  
Beginning of Period ................. $9.63         $9.78        $8.91       $10.21        $9.92        $9.56
                                      -----         -----        -----       ------        -----        -----
Income From Investment Operations
  Net Investment Income .............  0.30          0.60         0.61         0.58         0.66         0.63
  Net Realized and Unrealized Gain
  (Loss) on Investment Transactions . (0.16)        (0.14)        0.87        (1.12)        1.88         0.35
                                      -----         -----        -----       ------        -----        -----
  Total From
  Investment Operations .............  0.14          0.46         1.48        (0.54)        2.54         0.98
                                      -----         -----        -----       ------        -----        -----
Distributions
  From Net Investment Income ........ (0.30)        (0.60)       (0.61)       (0.58)       (0.66)       (0.62)
  From Net Realized Gains on
  Investment Transactions ........... (0.09)        (0.01)       --           (0.18)       (1.59)       --
                                      -----         -----        -----       ------        -----        -----
  Total Distributions ............... (0.39)        (0.61)       (0.61)       (0.76)       (2.25)       (0.62)
                                      -----         -----        -----       ------        -----        -----
Net Asset Value, End of Period ...... $9.38         $9.63        $9.78        $8.91       $10.21        $9.92
                                      =====         =====        =====        =====       ======        =====
  Total Return(3) ...................  1.45%         4.91%       17.16%       (5.47%)      11.81%       10.40%

RATIOS/SUPPLEMENTAL DATA
Ratio of Operating Expenses
to Average Net Assets ...............0.80%(4)       0.79%        0.78%         0.88%        1.00%      0.98%(5)
Ratio of Net Investment Income
to Average Net Assets ...............6.27%(4)       6.18%        6.53%         6.07%        6.54%        6.30%
Portfolio Turnover Rate .............    27%         100%         105%           78%         113%         186%
Net Assets, End
of Period (in thousands) ...........$128,173    $142,567     $149,223      $121,012     $172,120      $154,031

(1)  Six months ended April 30, 1997 (unaudited).

(2)  The data  presented  has been  restated  to give effect to a 10 for 1 stock
     split in the form of a stock dividend that occurred on November 13, 1993.

(3)  Total  return   assumes   reinvestment   of  dividends  and  capital  gains
     distributions, if any. Total returns for periods less than one year are not
     annualized.

(4)  Annualized.

(5)  Expenses  are shown  net of  management  fees  waived  by the  manager  for
     low-balance account fees collected during the period.
</TABLE>

See Notes to Financial Statements


32   Financial Highlights                           American Century Investments


                         RETIREMENT ACCOUNT INFORMATION

As required by law, any distributions you receive from an IRA and certain 403(b)
distributions  [not  eligible for  rollover to an IRA or to another  403(b)] are
subject to federal income tax withholding at the rate of 10% of the total amount
withdrawn,  unless you elect not to have withholding apply. If you don't want us
to withhold  on this  amount,  you may send us a written  notice not to have the
federal  income tax withheld.  Your written  notice is valid for six months from
the date of  receipt  at  American  Century.  Even if you plan to roll  over the
amount you withdraw to another tax-deferred  account, the withholding rate still
applies to the withdrawn  amount unless we have received a written notice not to
withhold federal income tax within six months prior to the withdrawal.

When  you plan to  withdraw,  you may  make  your  election  by  completing  our
Exchange/  Redemption form or an IRS Form W-4P. Call American Century for either
form.  Your  written  election  is valid  for only six  months  from the date of
receipt at American Century. You may revoke your election at any time by sending
a written notice to us.

Remember,  even if you elect not to have income tax withheld, you are liable for
paying income tax on the taxable portion of your withdrawal. If you elect not to
have income tax withheld or you don't have enough income tax  withheld,  you may
be responsible  for payment of estimated tax. You may incur  penalties under the
estimated  tax rules if your  withholding  and  estimated  tax  payments are not
sufficient.


Semiannual Report                            Retirement Account Information   33


                                     NOTES


34   Notes                                          American Century Investments


                                     NOTES


Semiannual Report                                                     Notes   35


                             BACKGROUND INFORMATION

Investment Philosophy & Policies

The Benham Group offers 42 fixed-income  funds,  ranging from money market funds
to long-term bond funds and including both taxable and tax-exempt funds.

Limited-Term  Bond is a variable-price  bond fund that seeks to provide interest
income by investing in a diversified portfolio of fixed-income  securities.  The
fund must maintain a weighted average maturity of 5 years or less.

Intermediate-Term  Bond is a  variable-price  bond  fund that  seeks to  provide
interest  income  by  investing  in  a  diversified  portfolio  of  fixed-income
securities. The fund must maintain a weighted average maturity of 3-10 years.

Benham Bond is a variable-price  bond fund that seeks to provide interest income
by investing in a diversified portfolio of fixed-income securities. The fund has
no weighted average maturity requirement,  but it is expected that the fund will
invest primarily in intermediate- and long-term bonds.

Comparative Indices

The  following  indices  are used in the  report  to  serve as fund  performance
comparisons. They are not investment products available for purchase.

The   Merrill   Lynch  1-  to  5  -Year   Government/   Corporate   Index  is  a
market-value-weighted  index  composed of corporate  and  Treasury  debt with an
overall  maturity of  approximately 3 years. The index consists of approximately
24% corporate debt and 76% government  debt. The corporate debt issues are rated
BBB or better by Standard & Poor's.

The  Lehman  Intermediate   Government/  Corporate  Index  includes  the  Lehman
Government Index and the Lehman Intermediate Corporate Bond Index, which reflect
the price  fluctuations  of U.S.  Treasury  and  government  agency  securities,
corporate bonds and Yankee bonds with maturities of 1-10 years.

The Lehman  Aggregate Bond Index is composed of the Lehman  Government/Corporate
Index and the Lehman  Mortgage-Backed  Securities  Index.  It reflects the price
fluctuations  of  Treasury   securities,   U.S.  government  agency  securities,
corporate bond issues and mortgage-backed securities.

Lipper Rankings

Lipper Analytical  Services,  Inc. is an independent mutual fund ranking service
that groups funds according to their investment  objectives.  Rankings are based
on average  annual  returns  for each fund in a given  category  for the periods
indicated. Rankings are not included for periods less than one year.

The Lipper category for the Diversified Bond funds are:

Short    Investment-Grade    Debt   Funds   (Limited-Term    Bond)--funds   with
dollar-weighted  average  maturities of 5 years or less that invest at least 65%
of their assets in investment-grade debt.

Intermediate  Investment-Grade Debt Funds (Intermediate-Term  Bond)-- funds with
dollar-weighted  average  maturities  of 5-10 years that  invest at least 65% of
their assets in investment-grade debt.

Corporate  Debt Funds Rated A (Benham  Bond)--funds  that invest at least 65% of
their assets in government issues or corporate debt issues rated A or better.

PORTFOLIO MANAGEMENT TEAM
Senior Portfolio Manager     Bud Hoops
Portfolio Manager            Jeff Houston


CREDIT RESEARCH TEAM
Credit Analysts              Edward Grant, Tanya Fleischer,
                             Michael Difley, Tom Vaiana,
                             John Walsh
Associate
Credit Analysts              Sudha Mani, Richard McClung


36   Background Information                         American Century Investments


                                    GLOSSARY

Returns

o    Total Return figures show the overall  percentage  change in the value of a
     hypothetical  investment  in the fund  and  assume  that all of the  fund's
     distributions are reinvested.

o    Average Annual  Returns  illustrate  the annually  compounded  returns that
     would have  produced  the  fund's  cumulative  total  returns if the fund's
     performance  had been  constant  over the  entire  period.  Average  annual
     returns smooth out variations in a fund's return;  they are not the same as
     fiscal year-by-year results. For fiscal year-by-year returns,  please refer
     to the "Financial Highlights" on pages 30-32.

Yields

o    30-day SEC Yield represents net investment income earned by the fund over a
     30-day period,  expressed as an annual  percentage rate based on the fund's
     share  price at the end of the  30-day  period.  The SEC  yield  should  be
     regarded as an estimate of the fund's rate of investment income, and it may
     not equal the fund's actual income  distribution rate, the income paid to a
     shareholder's  account,  or the income  reported  in the  fund's  financial
     statements.

Portfolio Statistics

o    Number of Securities--the  number of different securities held by a fund on
     a given date.

o    Weighted  Average  Maturity  (WAM)--a  measurement of the  sensitivity of a
     fixed-income  portfolio to interest rate changes. WAM indicates the average
     time until the  securities  in the  portfolio  mature,  weighted  by dollar
     amount. The longer the WAM, the more interest rate exposure and sensitivity
     the portfolio has.

o    Average  Duration--another  measure of the  sensitivity  of a  fixed-income
     portfolio to interest rate changes.  Duration is a time-weighted average of
     the interest and principal  payments of the  securities in a portfolio.  As
     the  duration of a portfolio  increases,  so does the impact of a change in
     interest rates on the value of the portfolio.

o    Expense  Ratio--the   operating  expenses  of  the  fund,  expressed  as  a
     percentage  of average  net assets.  Shareholders  pay an annual fee to the
     investment  manager for investment  advisory and management  services.  The
     expenses and fees are deducted from fund income,  not from each shareholder
     account. (See Note 2 in the Notes to Financial Statements.)

Types of Fixed-Income Securities

o    Corporate  Bonds--debt  securities or  instruments  issued by companies and
     corporations.  Short-term corporate securities are tyically issued to raise
     cash and  cover  current  expenses  in  anticipation  of  future  revenues;
     long-term corporate securities are issued to finance capital  expenditures,
     such as new plant construction or equipment purchases.

o    Foreign  Government  Securities--debt  securities  issued or  guaranteed by
     foreign  governments  or  their  political  subdivisions.   Some  of  these
     securities  are direct  obligations of the issuing  government;  others are
     backed by some form of government sponsorship.

o    Mortgage-Backed  Securities--debt  securities  that represent  ownership in
     pools of mortgage loans. Most mortgage-backed  securities are structured as
     "pass-throughs"--the  monthly  payments of  principal  and  interest on the
     mortgages  in the pool are  collected  by the bank  that is  servicing  the
     mortgages  and are "passed  through" to  investors.  While the  payments of
     principal and interest are considered secure (many are backed by government
     agency   guarantees),   the  cash  flow  is  less  certain  than  in  other
     fixed-income  investments.  Mortgages that are paid off early reduce future
     interest payments from the pool.

o    U.S.   Government  Agency   Securities--debt   securities  issued  by  U.S.
     government  agencies  (such as the  Federal  Home Loan Bank and the Federal
     Farm Credit Bank).  Government  agency  securities  include  discount notes
     (maturing in one year or less) and medium-term notes,  debentures and bonds
     (maturing in three months to 50 years).

o    U.S. Treasury  Securities--debt  securities issued by the U.S. Treasury and
     backed by the direct "full faith and credit" pledge of the U.S. government.
     Treasury  securities  include bills  (maturing in one year or less),  notes
     (maturing in two to 10 years) and bonds (maturing in more than 10 years).


Semiannual Report                                                  Glossary   37


[american century logo]
American
Century(sm)

P.O. Box 419200
Kansas City, Missouri
64141-6200

Investor Services:
1-800-345-2021 or 816-531-5575

Automated Information Line:
1-800-345-8765

Telecommunications Device for the Deaf:
1-800-634-4113 or 816-444-3485

Fax: 816-340-7962

Internet: www.americancentury.com


AMERICAN CENTURY MUTUAL FUNDS, INC.

Investment Manager
AMERICAN CENTURY INVESTMENT MANAGEMENT


This  report and the  statements  it  contains  are  submitted  for the  general
information of our  shareholders.  The report is not authorized for distribution
to  prospective  investors  unless  preceded  or  accompanied  by  an  effective
prospectus.

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