First, the study examined the nature of high school prevention programs and the goals and methods of their curricula in the California CAPTA (Child Abuse Prevention and Training Act) programs and, for comparison, in other states. The effectiveness of the high school CAPTA programs in teaching students new skills, knowledge, and behaviors to avoid abuse was assessed with student questionnaires and by interviews with students, parents, CAPTA staff, high school staff, and child protective service and law enforcement staff. The retention of this learning was tested. The impact of child abuse prevention programs on high school youth from various cultural and ethnic groups; on school personnel, parents, and protective service and police agencies; and on relationships between school and community prevention efforts was estimated. Lessons are drawn for more productive and efficient prevention programs in schools and in the community. 240 references, subject index.