1 Exhibit 11 ITT EDUCATIONAL SERVICES, INC. COMPUTATION OF BASIC AND DILUTED EARNINGS PER SHARE (IN THOUSANDS, EXCEPT PER SHARE DATA) THREE MONTHS ENDED MARCH 31, ------------------------------ 1998 1997 ------ ------ Net income $ 7,328 $ 6,202 ======== ======== Shares: Weighted average number of shares of common stock outstanding 27,000 27,000 Shares assumed issued (less shares assumed purchased for treasury) on stock options 144 109 -------- -------- Outstanding shares for primary earnings per share calculation 27,144 27,109 ======== ======== Earnings per common share: $ 0.27 $ 0.23 ======== ========