SECURITIES AND EXCHANGE COMMISSION

                             Washington, D.C. 20549

                                    FORM 8-K

                                 CURRENT REPORT

                Pursuant to Section 13 or 15(d) of the Securities
                              Exchange Act of 1934


                Date of Report (Date of earliest event reported):
                                  May 26, 2005
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                              SPARTECH CORPORATION
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             (Exact name of registrant as specified in its charter)

                                    DELAWARE
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                 (State or other jurisdiction of incorporation)

                   1-5911                        43-0761773
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           (Commission File Number)  (IRS Employer Identification No.)

          120 South Central Avenue, Suite 1700, Clayton, Missouri 63105
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          (Address of principal executive offices)           (Zip Code)

                                 (314) 721-4242
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              (Registrant's Telephone Number, Including Area Code)

Check the appropriate box below if the Form 8-K is intended to simultaneously
satisfy the filing obligation of the registrant under any of the following
provisions (see General Instructions A.2. below):

    [ ] Written communications pursuant to Rule 425 under the Securities Act
        (17 CFR230.425)

    [ ] Soliciting material pursuant to Rule 14a-12 under the Exchange Act
        (17 CFR 240.14a-12)

    [ ] Pre-commencement communications pursuant to Rule 14d-2(b) under the
        Exchange Act (17 CFR 240.14d-2(b))

    [ ] Pre-commencement communications pursuant to Rule 13e-4(c) under the
        Exchange Act (17 CFR 240.13e-4(c))






                              SPARTECH CORPORATION

                                    FORM 8-K



Item 1.01. Entry into a Material Definitive Agreement.
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(a) On May 26, 2005 Spartech Corporation entered into a Retirement Agreement
with its former Chairman, President and CEO, Bradley B. Buechler, who had
resigned effective May 6, 2005.

The Company's Board of Directors approved a draft of the Retirement Agreement
prepared by Kirkpatrick & Lockhart Nicholson Graham LLP, counsel to the
independent directors and the Compensation Committee of the Board, at a meeting
held on May 9, 2005. The Board also authorized the Compensation Committee of the
Board to review and approve the final Retirement Agreement including any changes
which it might deem advisable based on negotiations with Mr. Buechler and his
attorney, some of which were subsequently made and so approved.

Pursuant to the Retirement Agreement, assuming it has not been rescinded by Mr.
Buechler during a seven-day rescission period expiring June 3, 2005:

        (i)   The Retirement Agreement will become non-terminable and will
              supersede and replace in its entirety Mr. Buechler's
              Amended and Restated Employment Agreement dated effective
              November 1, 2002 (the "Employment Agreement");

        (ii)  The Company will immediately pay Mr. Buechler the sum of
              $2,711,174 in full satisfaction of any obligation for severance
              benefits under the Employment Agreement or otherwise, plus
              $35,686 in accrued vacation pay;

        (iii) The Company will pay Mr. Buechler as a deferred retirement
              payment a sum equal to 216/365 of the fiscal 2005 bonus to which
              he would be entitled under his Employment Agreement, payable when
              he would have become entitled to such bonus;

        (iv)  The Company will transfer to Mr. Buechler the life insurance
              policy currently owned and maintained by the Company as funding
              for the deferred compensation provided for Mr. Buechler under the
              Employment Agreement, and Mr. Buechler will continue to be
              entitled to such benefits as he is entitled to under the terms of
              any other employee benefit plans applicable to him;

        (v)   For a period of three years, the Company will continue to provide
              coverage to Mr. Buechler and his dependents under the Company's
              health benefit and life insurance programs in effect from time to
              time, on the same terms and conditions and subject to the same
              employee contribution rates as the Company provides for its other
              employees;

        (vi)  Mr. Buechler's vested stock options will continue to be
              exercisable for their remaining terms; however, his unvested
              stock options will never become exercisable and will terminate;
              and





        (vii) The Company will transfer to Mr. Buechler the automobile
              currently leased for him by the Company as well as his office
              furniture and furnishings, and will permit him to use the
              Company's aircraft for personal use until June 7, 2005 subject to
              the Company's existing policies regarding reimbursement for such
              use.

To the extent the above payments are subject to tax withholding, the Company
will withhold applicable taxes from the cash portion of such payments.

The Retirement Agreement also includes a full release of the Company by Mr.
Buechler, and covenants by Mr. Buechler not to compete with Spartech or solicit
its employees or business for a period of two years and not to assist any
attempt at a hostile takeover of Spartech for a period of three years.



Item 1.02. Termination of a Material Definitive Agreement.
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On June 3, 2005, when Mr. Buechler's Retirement Agreement becomes
non-terminable, Mr. Buechler's Amended and Restated Employment Agreement dated
effective November 1, 2002 will be superseded and effectively terminated, as
more fully described in Item 1.01 above. Upon termination of the Employment
Agreement, Mr. Buechler will have no rights to receive any further salary, bonus
or other compensation or benefits from the Company other than as provided in the
Retirement Agreement. In addition, the Company will no longer be required to
repurchase or register for sale any of Mr. Buechler's shares of the Company,
provisions for which were provided in the Employment Agreement.






                                   SIGNATURES


Pursuant to the requirements of the Securities Exchange Act of 1934, the
registrant has duly caused this report to be signed on its behalf by the
undersigned hereunto duly authorized.


                              SPARTECH CORPORATION

Date May 31, 2005           By /s/ RANDY C. MARTIN
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                               Randy C. Martin
                               Executive Vice President - Corporate Development
                                    and Chief Financial Officer