1 st Quarter 2005 Conference Call March 8, 2005

Presentation Content Forward Looking Statements: Information presented contains certain forward-looking statements, defined in Section 21E of the Securities Exchange Act of Forward-looking statements represent our judgment relating to, among other things, future results of operations, growth plans, sales, capital requirements and general industry and business conditions applicable to us. They are based largely on our current expectations. Our actual results could differ materially from the information contained in the forward-looking statements due to a number of factors, including changes in the availability and cost of raw materials, changes in the economy or the plastics industry in general, other unanticipated events that may prevent us from competing successfully in existing or new markets, and our ability to manage our growth effectively. Investors are also directed to the discussion of risks and uncertainties associated with forward-looking statements contained in our Annual Report on Form 10-K filed with the Securities and Exchange Commission.

Investment Highlights… 1 st Quarter 2005 Results Investment Highlights u Market Leader in Sheet u Diversified Products & End-Use Markets u Solid Historical Performance…53 Consecutive Profitable Quarters u Accountability Based Culture of Innovation & Productivity with Experienced Management Team u Growth Strategy Combines New Product Developments with Domestic & Global Expansions 1 st Quarter 2005 Results Net Sales $305 mil. …26% increase over ‘04 Op. Earnings $10.3 mil. …3.4% of Sales or 3¢ per pound shipped Diluted EPS$.09/sh. …vs $.26/sh last yr Quarterly Dividend … $.12/share

Sales Fluctuations (Last Five Quarters)... Internal Volume/Acquisition/Price-Mix 1 st Qtr 4 th Qtr 3 rd Qtr2 nd Qtr 1 st Qtr FY FY Int Vol 3% 11%15% 9% 5% 9% 1% Acq 10% 6% 3% 4% 4% 4% 3% Prc/Mx 13% 3% 3% 2% 4% 4% 2% Total 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 [1 st Qtr Actual] st Quarter Sales of $305 Million and 340 Million Pounds Packaging 23% Transportation 23% Rec. & Leisure 11% Bldg. & Const. 13% Other 10% 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

Spartech Operating Results… Operating Earnings Per Pound Shipped ¢ Operating Earnings Per Pound First Quarter ¢ ¢ ¢ ¢

MISSION STATEMENT INTEGRATED MANAGEMENT SYSTEM Culture --- Philosophy --- Strategy… Mission -- To Generate Integrity-Based Shareholder Value CULTURE PHILOSOPHY TTQ ‘90 TOS ‘92 GEP ‘94 GTT ‘96 GFC ‘00 Four Cornerstones Three Pyramids “Growth with Integrity” ‘02 “Accountable and Lean” ‘03 Committed to Generating Value For…Customers, Shareholders, Employees TCS ‘98 STRATEGY “Investing in…P.P.T.G” ‘04 CPC ‘01

Outsourcing Acquisitions… Transactions Completed Last Two Years Date Company Vol (Lbs) Business/SegmentSEH Producing Location Dec ‘01MTD-Cleveland 5 Mil M & P…S-IndustriesTupelo, MS April ‘02Whirlpool-Mexico 26 Mil S & R…S-PlasticsRamos-Arizpe, Mexico July ’02MAAX-Canada 7 Mil S & R…S-PlasticsGranby, Can. Jan ’03G. Lakes-Ohio 22 Mil C & C…S-PolycomArlington, TX Sept ’03TriEnda-Portage 40 Mil S & R…S-PlasticsPortage, WI Jan ‘04QPS-Midwest 6 Mil S & R…S-PlasticsGreenville, OH; Richmond, IN April ‘04BASF- FR & Antistat 15 Mil C & C…S PolycomDonchery, France 121Mil+

International Expansion Activities… Outlook for Next Two Years Location Vol (Lbs) Business Segment Status...Future Potential Mexico 55 Mil France 65 Mil China N/A* Europe N/A * Est Vol ~ 50Mil In 1 st Yr S & R…C & C C & C...S & R All Three Segments S & R…C & C Commenced Full Production …April 2003 New Visteon Tank Contract …16 Mil Lbs To Start 9/04 Made Week Long Visit In Oct, with another follow up visit scheduled for early Sept. …Shanghai Area Likely Site Have Held Few Discussions....Southern Europe Potential

Focused Growth… Organic Growth Via Innovative New Products Introduced New Class of Ten Alloy Plastics--April 2004 Introduced Volume II of Product Transformations Brochure--June 2003

Growth Thru Product Transformations … Recognizable PT’s Over Last 8 Years Packaging Appliance & Hardware Recreation & Leisure Transportation Building & Construction

Business Partnership Enhancement Effort… New Centralized Product Development Center - ’04 u A Spartech Centralized Product Development Center Located at Our Warsaw, Indiana Facility; Opened June 2004: »Purpose – To Develop New Products In One Plant Alleviating Stress On Manufacturing Sites To Double As Development Centers »Structure – Will House Two Sheet Lines, VEC Cell, & Two Test Thermoformers To Allow For The Testing Of Various Materials  Benefits Of Centralized R & D Location Will Include: »Improved Production Efficiencies…At Current Manufacturing Sites »Centralized Knowledge Base…On New Product Development »Further Integration…Of S & R And C & C Groups »Accelerate New Products To Market…Both Potential PT’s & Samples

Focused Internal Growth from New Products… Alloy Plastics Drive Product Transformations 54 Alloy Plastics471 Product Transformations New Products = 16% of First Qtr ‘05 Sales of $305 Mil ($48Mil) vs. 17% of ‘04 Sales of $241 Mil ($41Mil) CAGR =36% Q05

Lean Business Enterprise… Strategy and Key Initiatives SUPPLY CHAIN MANAGEMENT SHOP FLOOR KAIZENS 6 SIGMA QUALITY ADVANCED PRODUCT DEVELOPMENT & MANUFACTURING SPARTECH LEAN ENTERPRISE Objectives :  Reduce Change Over Time  Yield Improvement  Scrap Reduction  Cycle Time Reduction  Improved Mfg Flexibility  Productivity Gains Benefits :  Lower Conversion Costs  Increase of Current Capacity  Higher Customer Satisfaction  Improved Cash Flows  Improved Lead Times Objectives :  Information Sharing  Kanban Implementation  Purchasing Leverage  Reduction in Suppliers  Corporate Purchasing Teams Benefits :  Reduced Supplier Lead Times  Reduced Freight Costs  Improved Material Costs  Improved Material Availability  Improved Material Quality Levels Objectives :  Formalized New Product Process  Faster Time to Market  Standardized Equipment  Smart Automation Benefits :  Lower Conversion Costs  Higher Customer Satisfaction  Improved Sales Growth  Improved Cash Flows Objectives :  Black & Green Belt Program  Improved Yields  Standardized Processes  Root Cause/Problem Solving  Improved Specifications  Total Productive Maintenance Benefits :  Lower Conversion Costs  Higher Customer Satisfaction  Improved Sales Growth  Improved Cash Flows

Total Debt to Total Debt and Equity... Current 1.1 To 1.0 Ratio 1 st Qtr

Operating Results for 1 st Qtr '05 Versus '04… Sales Up 26% and Net Earnings Down 63% ($’s In Millions, Except Per Share Data) Sales (  26%) Operating Earnings (  45%) Operating Earnings Per # (  52%).. Interest Costs (  2%) Net Earnings (  63%) Diluted EPS (  65%) $304.5 $ ¢ $ 6.5 $ 2.8 $.09/Sh 2004 $241.5 $ ¢ $ 6.3 $ 7.7 $.26/Sh

Spartech Corporation: “Good to Great”… 2005 Financial & Operating Goals row…Global Sales – Both Internally And Thru Acquisitions – To Produce A 12-15% Sales Increase in 2005…1 st Qtr ’05=13% (3% Internal/10% Acquisition) esults …Target Is To  Operating Earnings Per Pound Shipped by.5¢ and Increase Earnings Per Share by 15-20%...Not achieved in 1 st Qtr ‘05 fficiently…Utilize Lean Concepts & ACT’s to  Production Capacity by 5-10% And Reduce Debt As CapEx Principally Used To Fund New Technology…Improving & Seasonal ccelerate…Efforts to Advance The Knowledge of our People & Expand Capabilities of our Information Technology System at a Faster Pace (Send Additional 30 People Thru MDT & Initiate Annual Sales Personnel Training)…In Process echnology…Advancements To  the Flow of Alloy Plastics & Product Transformations to Market Thru New Technology Developments at our Product Development Center (Complete 12 Successful Programs in 2005) …In Process GREATGREAT

Key Operating Theme for 2005… Investing In “P-P-T-G” Strategy MDT MLB PDC AAE

Spartech Investment Highlights… Market Leader With Solid Growth Strategy  Leader In Custom Sheet Market –North American leader with more than 25% share of custom market  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  Solid Historical Performance/Outlook –Nine consecutive years of improved earnings performance ( ) –Solid performance in difficult economy ( )… positioned for future   New Outsourcing & International Opportunities –1 st Generation Outsourcing Trend Now Occurring –Vita’s Departure Opens Up International Opportunities  Solid Growth Story –New Products represent 17% of Sales For Fiscal 2004 –25 Acquisitions In Last 12 Years –Operating Management Bonuses Linked To 2005 Goals

1 st Quarter 2005 Conference Call March 8, 2005