This study examined the impact of a classroom-based, 10-week, cognitive-behavioral, anger management program plus booster sessions on middle school students with emotional disorders attending a therapeutic day school. Forty-five students were in the study; 20 received the program. The program group completed significantly more anger logs compared to the nonprogram group in both program and follow-up periods. Program students were observed to exhibit significantly more prosocial behaviors toward their teachers and showed a trend toward exhibiting fewer negative behaviors toward peers than nonprogram students at the end of the program. Program students also showed a trend toward fewer aggressive incidents than their nonprogram peers during follow-up. Findings may suggest mechanisms of change in anger management. (Contains 3 tables.)