This is a report of outcome of an alternative activity treatment program, consisting of off-campus supportive life skill activities, in a private vocational high school for court-adjudicated delinquent boys. A total of 130 adolescent male drug abusing student-clients were evaluated at follow-up, 22 months after admission to the day school treatment program. The determination of graduation vs. dropping out was made 3 years after admission to the study. The sample was 75% white, 21% black, and 4% Hispanic. Eighty-two percent were from 16 to 18 years of age, but only 24% had completed the 10th grade. The mean number of different types of drugs "ever used" was 5.87, and the mean number of drug sale offenses was 4.4. Sixty-one percent had been incarcerated (overnight or longer). A comprehensive assessment was administered at admission and at follow-up. The findings developed by paired t-test, comparing the student-clients' self-reports at follow-up evaluation with their self-reports at pretreatment, indicated significant improvement in numerous problem areas of behavior, adjustment, and attitude measured, except that no significant reduction in illicit drug use occurred. The improvement, however, was more related to the vocational training and job placement program and the general milieu of the school than to the off-campus supportive life skills program. The latter was shown to have a highly significant positive association with outcome as measured by success in graduating from high school and a significant positive association to improvement in "personal adjustment" (reduction in personal problems and increase in interpersonal maturity).(ABSTRACT TRUNCATED AT 250 WORDS)