The program provided students with sexuality and contraceptive education, individual and group counseling, and medical and contraceptive services over a period of almost 3 school years. Students in one other junior high school and another senior high school did not receive the services but provided baseline and end-of-project data and served as the control sample. The evaluation, built into the project from the outset, was based on aggregate data collected from the students through self-administered questionnaires. The questionnaires asked the students for detailed information on their knowledge, attitudes, and behavior relative to sexual conduct, contraception, and teenage pregnancy and parenthood. It also asked them about communication with their parents and partners, their educational aspirations, and a range of demographic and background variables. Over the 2 1/2 years of the program, changes in sexual and contraceptive knowledge occurred among participants. The program apparently created an atmosphere that allowed teenagers to translate their attitudes into counteractive preventive behavior. 4 tables, 7 references.