EXHIBIT 11 SPARTECH CORPORATION AND SUBSIDIARIES STATEMENT RE COMPUTATION OF PER SHARE EARNINGS (In thousands, except per share data) QUARTER ENDED SIX MONTHS ENDED May 2, May 3, May 2, May 3, 1998 1997 1998 1997 NET EARNINGS Basic and diluted net earnings $ 8,863 $ 6,675 $ 15,884 $ 12,153 WEIGHTED AVERAGE SHARES OUTSTANDING Basic weighted average common shares outstanding 26,764 26,387 26,611 26,385 Add: Shares issuable from assumed exercise of options 1,964 1,370 1,834 1,362 Diluted weighted average 28,728 27,757 28,445 27,747 shares outstanding NET EARNINGS PER SHARE Basic $ .33 $ .25 $ .60 $ .46 Diluted $ .31 $ .24 $ .56 $ .44