Media literacy education teaches youth to critically examine the influence of media messages on health and substance use behavior. A small group of low-achieving middle school students at high risk for substance abuse attending an afterschool academic remediation program received a media literacy intervention intended for elementary students in a classroom setting. Participants significantly increased their: preferences for non-alcohol-related advertisements, ability to identify advertising techniques, media deconstruction skills, negative opinions about drinking and smoking behaviors, and significantly decreased their positive perceptions of cigarette and alcohol content in advertising. Results suggest that the Media Detective Program, an elementary-level, classroom-based intervention, can improve outcomes for at-risk middle school students in the afterschool setting.