Disruptive behaviors such as elopement, calling-out, and aggression are often a major barrier to instruction in preschool classrooms. One widely used class-wide behavior management system used to decrease disruptive behaviors and increase on-task behavior is Class-Wide Function-Related Intervention Teams (CW-FIT). CW-FIT was originally designed to be used for classrooms kindergarten through 5th grade, however, this paper session will describe two research projects designed to evaluate the effectiveness of CW-FIT in preschool settings. The first study was conducted to assess the efficacy of CW-FIT in increasing the on-task behavior of students and improving teacher behavior in a preschool classroom and to evaluate these effects in separate large and small group settings. Results suggest that CW-FIT increased on-task group behavior in both the large and small group settings. Results for rates of teacher’s praise and reprimand statements were, however, variable for the two settings. The second study (in progress) will evaluate the differentiated effects of the traditional CW-FIT using an interdependent group contingency and a modified CW-FIT using a dependent group contingency on on-task student behavior and teacher behaviors. It is hypothesized that both versions will show equal improvement in student and teacher behaviors, but that teachers will prefer the modified version.