The majority of students with disabilities and behavioral challenges are taught in general education classrooms. Although these students may receive interventions resulting in positive behavioral changes, little is known about the collateral effects of implementing behavior intervention plans (BIP) on classroom peers with similar behavioral problems who are not receiving an intervention. The purpose of this study was to investigate the effects of functional behavioral assessments (FBAs) and BIPs for students with challenging behavior as well as their peers. We measured target student and peer academic engagement, as well as treatment integrity and social validity. As a result of the intervention, target students demonstrated increased academic engagement. In addition, results suggest that the FBA-BIPs had small effects on engagement for some peers.