Compared to the children who did not participate in ACT, program participants showed significant improvement in coping responses, problem-solving skills, prosocial skills, and nonaggressive classroom behaviors. Thus, the program was successful in changing children's attitudes and perceptions underlying their physical aggression, such as difficulty in sustaining and focusing attention, expectation of hostile intent from others, and poor problem-solving abilities. Based on individual assessments of the 12 children selected for participation in the ACT program, researchers identified 9 categories of irrational beliefs underlying childhood aggression. These were addressed in the cognitive-behavioral therapy provided to parents and children in the ACT program. The evaluative research involved experimental and control groups with precomparison and postcomparison assessments. Qualitative data were collected through 367 individual interviews with children, parents, and teachers. The interviews focused on the children's cognitive (attitudes and perceptions) characteristics and aggressive behaviors at home and at school. Two pilot studies and a main study were conducted. 2 tables and 72 references