A 12th grade follow-up assessed the long-term effects of substance abuse prevention efforts delivered in sixth and seventh grades. A social pressures resistance skills curriculum implemented by classroom teachers had been evaluated with short-term positive results previously reported. Students completed self-administered questionnaires at 6th grade pre- and posttests, and at 7th and 12th grade posttests. Curriculum group students received lessons on alcohol, tobacco, marijuana, and cocaine, which were later incorporated into the Michigan Model for Comprehensive School Health Education. This evaluation used data from 262 students who completed all four questionnaires and who received the complete 2-year intervention or no intervention. Significant effects evident at 7th grade for alcohol use and misuse, as well as cigarette, cocaine and other drug use were generally not maintained through 12th grade. Tables, figure, references