Using the National Education Longitudinal Study (NELS) data set from the 1988-1992 period, this study used longitudinal data to assess the effects of student religious commitment on the marijuana, cocaine, and alcohol consumption of those children. The results of this study support the notion that a high level of religious commitment among adolescents reduces their likelihood of consuming marijuana, cocaine, and alcohol. Religiously committed adolescents consumed marijuana, cocaine, and alcohol less frequently and were less likely to be under the influence of marijuana and alcohol at school than their less religious counterparts. There were, however, no differences in the likelihood of religious and less religious twelfth graders to be under the influence of cocaine while at school. The study also indicates that the use of marijuana, cocaine, and alcohol by adolescents was associated with lower levels of academic achievement than those students who did not use these substances.