Middle school students with social and behavioral concerns need additional support. The current study investigated the effects of Class-Wide Function-related intervention teams adapted for middle school contexts (CW-FIT MS) and self-management (SM) in a sixth-grade reading class. CW-FIT MS was implemented, subsequently, for students with data indicating additional support was needed, and a self-management component was added to intensify the intervention (CW-FIT MS w/ SM). A single-subject multiple baseline design was implemented across four student participants, and the on-task student behavior as well as the teacher-student relationship were examined to assess the effects of the intervention. Results indicated improved on-task behavior for three of four students with the implementation of the self-management intervention, demonstrating promising maintenance effects. Preliminary data showed an overall improvement in the teacher-student relationship. Both teachers and students reported positive perceptions about the intervention, consistent with earlier findings in CW-FIT MS studies. Limitations and areas for future research are addressed. [For the Grantee Submission, see ED616821.]