SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, DC 20549

SCHEDULE TO/A

(Rule 14d-100)
TENDER OFFER STATEMENT UNDER SECTION 14(d)(1) OR 13(e)(1)
OF THE SECURITIES EXCHANGE ACT OF 1934

(Amendment No. 1)

WINTHROP GROWTH INVESTORS 1 LIMITED PARTNERSHIP
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(Name of Subject Company (Issuer))

AIMCO PROPERTIES, L.P. - OFFEROR
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(Names of Filing Persons (Identifying Status as Offeror, Issuer or Other Person)

LIMITED PARTNERSHIP UNITS
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(Title of Class of Securities)

NONE
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(CUSIP Number of Class of Securities)

Patrick J. Foye
Executive Vice President
Apartment Investment and Management Company
Colorado Center, Tower Two
2000 South Colorado Boulevard, Suite 2-1000
Denver, Colorado 80222
(303) 757-8081
- --------------------------------------------------------------------------------
(Name Address and Telephone Number of Person
Authorized to Receive Notices and Communications on Behalf of Filing Persons)

Copy To:
Gregory M. Chait
Robert Barker
Powell, Goldstein, Frazer & Murphy LLP
191 Peachtree Street, N.E., Sixteenth Floor
Atlanta, Georgia 30303
(404) 572-6600

CALCULATION OF FILING FEE
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<Caption>
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Transaction Valuation* Amount of Filing Fee**
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$5,923,584 $544.97
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* For purposes of calculating the fee only.

** Previously paid.

[ ] Check the box if any part of the fee is offset as provided by Rule
0-11(a)(2) and identify the filing with which the offsetting fee was
previously paid. Identify the previous filing by registration statement
number, or the Form or Schedule and the date of its filing.

Amount Previously Paid: Filing Party:
------------------ -----------------

Form or Registration No.: Date Filed:
---------------- -------------------

[ ] Check the box if the filing relates solely to preliminary communications
made before the commencement of a tender offer.

Check the appropriate boxes below to designate any transactions to which
the statement relates:

<Table>

[X] third-party tender offer subject to Rule 14d-1. [ ] going-private transaction subject to Rule 13e-3.

[ ] issuer tender offer subject to Rule 13e-4. [ ] amendment to Schedule 13D under Rule 13d-2.
</Table>

Check the following box if the filing is a final amendment reporting the
results of the tender offer: [ ]

TENDER OFFER STATEMENT

This amendment amends the Tender Offer Statement on Schedule TO filed
by AIMCO Properties, L.P., a Delaware limited partnership ("AIMCO Properties"),
in connection with its tender offer to purchase outstanding units of limited
partnership interest of Winthrop Growth Investors 1 Limited Partnership, a
Massachusetts limited partnership, at a price of $512.00 per unit in cash,
subject to the conditions set forth in the Offer to Purchase, dated August 20,
2002 (the "Offer to Purchase"), and in the related Letter of Transmittal and
Acknowledgment and Agreement, which, as amended and supplemented from time to
time, together constitute the tender offer. Copies of the Offer to Purchase,
Letter of Transmittal and Acknowledgment and Agreement are filed with this
Schedule TO as Exhibits (a)(1), (a)(2) and (a)(3), respectively. The item
numbers and responses thereto below are in accordance with the requirements of
Schedule TO.

On September 17, 2002, AIMCO Properties mailed a letter to the holders
of units of Winthrop Growth Investors 1 Limited Partnership, announcing that it
was extending the expiration date of the offer from midnight New York time on
September 17, 2002, to midnight New York time September 27, 2002. A copy of that
letter is filed with this Schedule TO as Exhibit (a)(7).

ITEM 1. SUMMARY TERM SHEET.

The information set forth under "Summary Term Sheet" in the Offer to
Purchase is incorporated herein by reference.

The bullet point entitled "No General Partner Recommendation" is hereby
replaced in its entirety with the following:

o NO GENERAL PARTNER RECOMMENDATION. The general partner makes
no recommendation as to whether you should tender or refrain
from tendering your units, and each limited partner should
make his or her own decision whether or not to tender. See
"The Offer--Section 10. Position of the General Partner of
your Partnership with respect to the Offer." Your general
partner does not believe that selling all or substantially all
of the Properties or liquidating the partnership would be in
the best interest of the unitholders. See "The Offer--Section
9. Background and Reasons for the Offer."

ITEM 2. SUBJECT COMPANY INFORMATION.

(a) - (c) The information set forth under "THE OFFER--Section 13.
Certain Information Concerning Your Partnership" in the Offer to Purchase is
incorporated herein by reference.

ITEM 3. IDENTITY AND BACKGROUND OF FILING PERSON.

(a) - (c) This Schedule TO is being filed by AIMCO Properties.
AIMCO-GP, Inc., a Delaware corporation ("AIMCO-GP"), is the general partner of
AIMCO Properties and a wholly owned subsidiary of Apartment Investment and
Management Company ("AIMCO"). The principal business of AIMCO, AIMCO-GP and
AIMCO Properties is the ownership, acquisition, development, expansion and
management of multi-family apartment properties. The business address of AIMCO
Properties is 2000 South Colorado Boulevard, Suite 2-1000, Denver, Colorado
80222, and its telephone number is (303) 757-8101.

The information set forth under "THE OFFER--Section 8. Information
Concerning Us and Certain of Our Affiliates" in the Offer to Purchase is
incorporated herein by reference.

During the past five years, none of AIMCO, AIMCO-GP or AIMCO
Properties, nor, to the best of their knowledge, any of the persons listed in
Annex I to the Offer to Purchase (i) has been convicted in a criminal proceeding
(excluding traffic violations or similar misdemeanors) or (ii) was a party to a
civil proceeding of a judicial or administrative body of competent jurisdiction
and as a result of such proceeding was or is subject to a judgment, decree or
final order enjoining future violations of, or prohibiting activities subject
to, federal or state securities laws, or finding any violation with respect to
such laws.

ITEM 4. TERMS OF THE TRANSACTION.

(a) The information set forth under "SUMMARY TERM SHEET" and "THE
OFFER" in the Offer to Purchase and the information set forth in the related
Letter of Transmittal is incorporated herein by reference.

On September 17, 2002, AIMCO Properties announced that it was extending
the offer period until midnight New York time, on September 27, 2002, and mailed
a letter to each holder of units in Winthrop Growth Investors 1 Limited
Partnership, a copy of which is attached hereto as Exhibit (a)(7). AIMCO
Properties reserves the right to further extend the offer, to amend the offer or
to terminate the offer, in each case in its discretion and in accordance with
the terms of the Offer to Purchase, as amended.

AIMCO Properties is seeking to acquire the maximum amount of units
allowed to be purchased under the partnership agreement, given its prohibition
on transferring units that exceed 50% of all transfers during the preceding
twelve months. Approximately 4.5% of the units of the partnership have been
transferred in the preceding 12 months.

The subsection entitled "Determination of Validity; Rejection of Units;
Waiver of Defects; No Obligation to Give Notice of Defects" in Section 3.
Procedure for Tendering Units is hereby replaced in its entirety by the
following:

All questions as to the validity, form, eligibility (including time of
receipt) and acceptance for payment of any tender of units pursuant to
our offer will be determined by us, in our reasonable discretion,
which determination shall be final and binding on all parties. We
reserve the absolute right to reject any or all

tenders of any particular unit determined by us not to be in proper
form or if the acceptance of or payment for that unit may, in the
opinion of our counsel, be unlawful. We also reserve the absolute right
to waive any defect or irregularity in any tender with respect to any
particular unit of any particular limited partner, and to waive or
amend any of the conditions of the offer that we are legally permitted
to waive as to the tender of any particular unit, provided that if we
waive any condition with respect to one unit, we will waive such
condition as to all units. Our interpretation of the terms and
conditions of the offer (including the acknowledgment and agreement and
the letter of transmittal) will be final and binding on all parties. No
tender of units will be deemed to have been validly made unless and
until all defects and irregularities have been cured or waived. Neither
we, the Information Agent, nor any other person will be under any duty
to give notification of any defects or irregularities in the tender of
any unit or will incur any liability for failure to give any such
notification.

The fifth bullet point under "The Offer - Section 13. Conditions of the
Offer" is hereby modified in its entirety to read:

o your partnership shall have, due to events beyond our direct
or indirect control, (i) changed, or authorized a change of,
the units or your partnership's capitalization, (ii) issued,
distributed, sold or pledged, or authorized, proposed or
announced the issuance, distribution, sale or pledge of (A)
any equity interests (including, without limitation, units),
or securities convertible into any such equity interests or
any rights, warrants or options to acquire any such equity
interests or convertible securities, or (B) any other
securities in respect of, in lieu of, or in substitution for
units outstanding on the date hereof, (iii) purchased or
otherwise acquired, or proposed or offered to purchase or
otherwise acquire, any outstanding units or other securities,
(iv) declared or paid any dividend or distribution on any
units or issued, authorized, recommended or proposed the
issuance of any other distribution in respect of the units,
whether payable in cash, securities or other property, (v)
authorized, recommended, proposed or announced an agreement,
or intention to enter into an agreement, with respect to any
merger, consolidation, liquidation or business combination,
any acquisition or disposition of a material amount of assets
or securities, or any release or relinquishment of any
material contract rights, or any comparable event, not in the
ordinary course of business, (vi) taken any action to
implement such a transaction previously authorized,
recommended, proposed or publicly announced, (vii) issued, or
announced its intention to issue, any debt securities, or
securities convertible into, or rights, warrants or options to
acquire, any debt securities, or incurred, or announced its
intention to incur, any debt other than in the ordinary course
of business and consistent with past practice, (viii)
authorized, recommended or proposed, or entered into, any
transaction which, in our reasonable judgment, has or could
have an adverse affect on the value of your partnership or the
units, (ix) proposed, adopted or authorized any amendment of
its organizational documents, (x) agreed in writing or
otherwise to take any of the foregoing actions or (xi) been
notified that any debt of your partnership or any of its
subsidiaries secured by any of its or their assets is in
default or has been accelerated;

ITEM 5. PAST CONTACTS, TRANSACTIONS, NEGOTIATIONS AND AGREEMENTS.

(a) and (b) The information set forth under "SUMMARY TERM
SHEET--Conflicts of Interest," "THE OFFER--Section 9. Background and Reasons for
the Offer" and "THE OFFER--Section 11. Conflicts of Interest and Transactions
with Affiliates" in the Offer to Purchase is incorporated herein by reference.

ITEM 6. PURPOSES OF THE TRANSACTION AND PLANS OR PROPOSALS.

(a), (c)(1) - (7) The information set forth under "SUMMARY TERM
SHEET--The Offer, "THE OFFER--Section 9. Background and Reasons for the Offer"
and "The Offer--Section 12. Future Plans of the Purchaser" in the Offer to
Purchase is incorporated herein by reference.

ITEM 7. SOURCE AND AMOUNT OF FUNDS OR OTHER CONSIDERATION.

(a), (b) and (d) The information set forth under "SUMMARY TERM
SHEET--Availability of Funds," "THE OFFER--Section 15. Source of Funds" and "THE
OFFER--Section 19. Fees and Expenses" in the Offer to Purchase is incorporated
herein by reference.

ITEM 8. INTEREST IN SECURITIES OF THE SUBJECT COMPANY.

The information set forth under "THE OFFER--Certain Information
Concerning Your Partnership" in the Offer to Purchase is incorporated herein by
reference.

ITEM 9. PERSONS/ASSETS, RETAINED, EMPLOYED, COMPENSATED OR USED.

The information set forth under "THE OFFER--Section 19. Fees and
Expenses" in the Offer to Purchase is incorporated herein by reference.

ITEM 10. FINANCIAL STATEMENTS.

(a) The financial statements included in AIMCO Properties' Annual
Report on Form 10-K for the year ended December 31, 2001, which are listed on
the Index to Financial Statements on page F-1 of such report, and the unaudited
financial statements for the six months ended June 30, 2002 and June 30, 2001
set forth in Part I, Item 1 of AIMCO Properties' Quarterly Report on Form 10-Q
for the quarter ended June 30, 2002, are incorporated herein by reference. Such
reports may be inspected at the Securities and Exchange Commission's public
reference room in Washington, D.C. A copy can also be obtained from the
Commission's web site at www.sec.gov.

(b) Not Applicable.

ITEM 11. ADDITIONAL INFORMATION.

The information set forth in the Offer to Purchase and in the related
Letter of Transmittal is incorporated herein by reference.

The following risk factor entitled "You may be unable to transfer your
units for a 12-month period" is hereby added to "Risk Factors":

Your partnership's agreement of limited partnership prohibits any
transfer of an interest if such transfer, together with all other
transfers during the preceding 12 months, would cause 50% or more of
the total interest in capital and profits of your partnership to be
transferred within such 12-month period. During the last 12 months,
approximately 4.5% of the total interest in capital and profits of your
partnership has been transferred. If more units are validly tendered
and not withdrawn, that would cause more than 50% of the total interest
in capital and profits of your partnership to be transferred within a
12-month period, we will accept for payment and pay for those units so
tendered pro rata according to the number of units so tendered, with
appropriate adjustments to avoid purchases of fractional units. If we
acquire a significant percentage of the interest in your partnership,
you may not be able to transfer your units for a 12-month period
following our offer.

The Risk Factor entitled "Continuation of the partnership; no time
frame regarding sale of partnership interests" is hereby supplemented by adding
the following new paragraph as the second paragraph:

Your general partner is of the view that the partnership agreement
would not permit a liquidation of the partnership prior to the sale of
all of the properties owned by your partnership. A liquidation prior to
the sale of the properties would expose the limited partners to
additional and unwarranted liabilities. For the reasons set forth
above, your general partner is of the opinion that a sale of the
properties would not be in the best interests of the limited partners.

"Section 9. Background and Reasons for the Offer - Alternatives
Considered by your General Partner" is hereby supplemented by adding the same
paragraph listed above.

ITEM 12. EXHIBITS.

(a)(1) Offer to Purchase limited partnership units of Winthrop Growth
Investors 1 Limited Partnership, dated August 20, 2002.
(Previously filed)

(a)(2) Letter of Transmittal and related instructions, dated August
20, 2002 (included as Annex II to the Offer to Purchase
attached as Exhibit (a)(1)).

(a)(3) Acknowledgement and Agreement, dated August 20, 2002.
(Previously filed)

(a)(4) Letter, dated August 20, 2002, from AIMCO Properties to the
limited partners of Winthrop Growth Investors 1 Limited
Partnership. (Previously filed)

(a)(5) Annual Report of AIMCO Properties for the year ended December
31, 2001 filed on Form 10-K405 on April 1, 2002 is
incorporated herein by reference.

(a)(6) Quarterly Report of AIMCO Properties for the period ended June
30, 2002 filed on Form 10-Q on August 14, 2002 is incorporated
herein by reference.

(a)(7) Letter, dated September 17, 2002, from AIMCO Properties, L.P.,
to the limited partners of Winthrop Growth Investors 1 Limited
Partnership.

(b)(1) Fourth Amended and Restated Credit Agreement, dated as of
March 11, 2002, by and among AIMCO Properties, AIMCO/Bethesda
Holdings, Inc., NHP Management Company, Bank of America, N.A.,
Fleet National Bank, First Union National Bank, and the other
financial institutions party thereto (Exhibit 10.29 to AIMCO's
Annual Report on Form 10-K for the year ended December 31,
2001 is incorporated herein by reference).

(b)(2) Second Amendment to Fourth Amended and Restated Credit
Agreement, dated as of August 2, 2002, by and among Apartment
Investment and Management Company, AIMCO Properties, L.P.,
AIMCO/Bethesda Holdings, Inc., NHP Management Company, Bank of
America, N.A. and the Lenders listed therein (Exhibit 10.2 to
AIMCO's Quarterly Report on Form 10-Q for the quarterly period
ended June 30, 2002 is incorporated herein by reference).

(d) Not applicable

(g) None.

(h) None.

ITEM 13. INFORMATION REQUIRED BY SCHEDULE 13E-3.

Not Applicable.

SIGNATURE

After due inquiry and to the best of its knowledge and belief, the
undersigned hereby certifies that the information set forth in this statement is
true, complete and correct.

Dated: September 17, 2002
AIMCO PROPERTIES, L.P.

By: AIMCO-GP, INC.
(General Partner)

By: /s/ Patrick J. Foye
----------------------------
Executive Vice President

EXHIBIT INDEX

<Table>
<Caption>
EXHIBIT NO. DESCRIPTION
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(a)(1) Offer to Purchase limited partnership units of
Winthrop Growth Investors 1 Limited Partnership,
dated August 20, 2002. (Previously filed)

(a)(2) Letter of Transmittal and related instructions, dated
August 20, 2002 (included as Annex II to the Offer to
Purchase attached as Exhibit (a)(1)).

(a)(3) Acknowledgement and Agreement, dated August 20, 2002.
(Previously filed)

(a)(4) Letter, dated August 20, 2002, from AIMCO Properties
to the limited partners of Winthrop Growth Investors
1 Limited Partnership. (Previously filed)

(a)(5) Annual Report of AIMCO Properties for the year ended
December 31, 2001 filed on Form 10-K405 on April 1,
2002 is incorporated herein by reference.

(a)(6) Quarterly Report of AIMCO Properties for the period
ended June 30, 2002 filed on Form 10-Q on August 14,
2002 is incorporated herein by reference.

(a)(7) Letter, dated September 17, 2002, from AIMCO
Properties, L.P., to the limited partners of Winthrop
Growth Investors 1 Limited Partnership.

(b)(1) Fourth Amended and Restated Credit Agreement, dated
as of March 11, 2002, by and among AIMCO Properties,
AIMCO/Bethesda Holdings, Inc., NHP Management
Company, Bank of America, N.A., Fleet National Bank,
First Union National Bank, and the other financial
institutions party thereto (Exhibit 10.29 to AIMCO's
Annual Report on Form 10-K for the year ended
December 31, 2001 is incorporated herein by
reference).

(b)(2) Second Amendment to Fourth Amended and Restated
Credit Agreement, dated as of August 2, 2002, by and
among Apartment Investment and Management Company,
AIMCO Properties, L.P., AIMCO/Bethesda Holdings,
Inc., NHP Management Company, Bank of America, N.A.
and the Lenders listed therein (Exhibit 10.2 to
AIMCO's Quarterly Report on Form 10-Q for the
quarterly period ended June 30, 2002 is incorporated
herein by reference).

(e) Not applicable

(i) None.

(j) None.
</Table>