3 rd Quarter 2005 Conference Call September 8, 2005

Presentation Content SPARTECH: FORWARD-LOOKING STATEMENTS This presentation contains "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995 that relate to future events and expectations. Forward-looking statements include those containing such words as "anticipates," "believes," "estimates," "expects," "would," "should,", "will," "will likely result," "forecast," "outlook," "projects," and similar expressions. Forward-looking statements are based on management's current expectations and include known and unknown risks, uncertainties and other factors, many of which management is unable to predict or control, that may cause actual results, performance or achievements to differ materially from those expressed or implied in the forward-looking statements. Important factors that could cause actual results to differ materially from those in the forward-looking statements include: (a) adverse changes in economic or industry conditions generally, including global supply and demand conditions and prices for products of the types produced by Spartech; (b) material adverse changes in the markets we serve, including the transportation, packaging, building and construction, recreation and leisure, and other markets, some of which tend to be cyclical; -continued-

Presentation Content SPARTECH: FORWARD-LOOKING STATEMENTS, continued (c) the inability to achieve the level of cost savings, productivity improvements, synergies, growth or other benefits anticipated from acquired businesses and their integration; (d) volatility of prices and availability of supply of energy and of the raw materials that are critical to the manufacture of our products, particularly plastic resins derived from oil and natural gas; (e) the inability to predict accurately the costs to be incurred or savings to be achieved in connection with announced production plant restructurings; (f) adverse findings in significant legal or environmental proceedings or the inability to comply with applicable environmental laws and regulations; (g) the inability to achieve operational efficiency goals or cost reduction initiatives; (h) the inability to develop and launch new products successfully (i) the inability to predict accurately the start-up costs associated with the new Donchery, France facility or the expansion of the existing wheels production capacity; (j) restrictions imposed on Spartech by instruments governing its indebtedness, and the possible inability to comply with requirements of those instruments, (k) weaknesses in internal controls; and (l) other risk factors summarized in reports filed by Spartech with the Securities and Exchange Commission. Spartech assumes no duty to update its forward-looking statements.

Investment Highlights… 3 rd Quarter 2005 Results Strategy Highlights u Capitalize on Market Leadership in Sheet and Diversified Products & Markets Served u Renewed Focus & Tracking of Cash Flow Generation u New Capital Expenditure Appropriation Process & Return on Investment Focus u A Process to Achieve World Class Service, Quality, & Cost 3 rd Quarter 2005 Results Net Sales $349 mil. …21% increase over ‘04 Op. Earnings $13.2 mil. …$21.6 excluding special items * Diluted EPS$.13 /sh. …vs $.30/sh excluding special items*, $.36 in ‘04 Quarterly Dividend … $.12/share * See slide reconciling GAAP to non-GAAP measures.

Sales Fluctuations (Last Seven Quarters)... Internal Volume/Acquisition/Price-Mix 3 rd Q nd Q st Q th Q rd Q nd Q st Q 2004 Fiscal Yr ‘ 04 Fiscal Yr ‘ 03 Internal-4%-1% 3% 11%15% 9% 5% 9% 1% Acquisition10%11%10% 6% 3% 4% 3% Price Mix15%21%13% 3% 2% 4% 2% Total21%31%26%20%21%15%13%17% 6%

Company Overview… Diversity of Products & Markets Key Base Materials... Comprehensive Product Portfolio [Full Year Estimate] Customer End Markets... Packaging Largest Sector [3 rd Qtr Actual] rd Quarter Sales of $349 Million and 365 Million Pounds Packaging 23% Transportation 22% Rec. & Leisure 11% Bldg. & Const. 15% Other 9% Lawn & Garden 6% Sign & Advertising 8% Appliances & Electronics 6% Polyethylene 25% Polystyrene 20% Polypropylene 15% ABS 10% PVC 10% Other--Specialty 20%

Sales Outlook… By “End Market” Application * The following represents rough guidelines for the Outlook Ratings above: Strong = +3% or higher growth; Flat = +/-2% change; Weak = -3% or more decline

Total Debt to Equity... Current 1.0 To 1 Ratio 3 rd Qtr 2 nd Qtr

Operating Results for 3 rd Qtr '05 Versus '04… Sales Up 21%, Net Earnings $4.3 Million ($’s In Millions, Except Per Share Data) Sales (  21%) Operating Earnings (  47%) Operating Earnings Excluding Special Items (  13%) * Interest Costs (  6%) Net Earnings Diluted EPS $348.7 $ 13.2 $ 21.6 $ 6.4 $ 4.3 $.13/Sh 2004 $288.0 $ 24.9 $ 24.9 $ 6.0 $ 11.7 $.36/Sh * See slide reconciling GAAP to non-GAAP measures.

Sales Data Trends Pounds Sold by Segment (Pounds in thousands)

Cash Flow Trends From Operations and Free Cash Flows (Dollars in thousands)

Material/Gross/Operating Margins Results on a per Pound Basis

Non-GAAP Measures GAAP to Non-GAAP Reconciliation Note: Management believes that operating earnings, net income, and earnings per share excluding special items, which are non-GAAP measurements, are meaningful to investors because they provide a view of the Company with respect to ongoing operating results. Special items (restructuring & exit costs, fixed asset charges, and the former CEO retirement) represent significant charges that are important to an understanding of the Company’s overall operating results in the periods presented. Such non-GAAP measurements are not recognized in accordance with generally accepted accounting principles (GAAP) and should not be viewed as an alternative to GAAP measures of performance. The following reconciles GAAP to non-GAAP measures for operating earnings, net income, and earnings per share excluding special items used within this presentation.

Leadership Transition… Ongoing Focus u Measures  Priorities on Key Measures  Tie measures to performance & compensation u Cost Reduction & Cash Flow Focus  Enhance profitability of operations (cost structure)  Improve working capital management u Returns  Capital Expenditures  Acquisitions  Resources/Investments Made –Volume Growth (market share) –CapEx (>$140M last 5 yrs) / Acquisitions –Technology / R&D

Spartech Investment Highlights… Market Leader With Solid Improvement Strategy  Leader In Key Custom Markets –North American leader in Sheet with more than 30% share of custom market –Top 5 In Compounding segment  Diversified End-Use Markets –Largest is non-cyclical Packaging market ~ 23% of sales –Largest customer represents less than 5% of sales –Continuing to expand end markets and product offerings  New Focus on Cost Control & Cash Flow Generation –Restructuring of operating locations –Continuous improvement of Working Capital Management –Accelerate cash flow to pay down debt  Renewed Focus on Return on Capital –Emphasis on working capital management –Capital expenditures for productivity & cost improvement –Compensation based on Operating Profit, Working Capital, & Sales Growth Metrics  World Class Service, Quality, & Costs –All metrics and rewards tied to these objectives (Corporate/Regional/Individual)

3 rd Quarter 2005 Conference Call September 8, 2005