Class-Wide Function-Related Intervention Teams (CW-FIT) is a classroom management system using a group contingency involving direct teaching of classroom rules/skills, differential reinforcement of appropriate behaviors, and minimized social attention to inappropriate behaviors. We investigated elementary school teachers' implementation of CW-FIT with minimal reliance on external researcher support. Nine teachers and their classes participated. Ten students nominated as at risk for emotional and behavioral disorders (EBD) were individually monitored. Effects were examined using a single case reversal design. During CW-FIT implementation teachers' use of praise increased and reprimands decreased, on-task behavior increased in all classrooms, and seven of the at-risk students also showed decreased disruptive behaviors. Teacher and student social validity ratings indicated support of and satisfaction with the program. Implications for classroom practice are discussed.