This article reports on a major action research program that experimented with the use of cross-age peer teaching in schools to assist teachers to manage conflict issues in their classrooms, and to re-engage disaffected students in learning. The research, which was conducted in a range of elementary and secondary schools in Australia, was part of a larger international project using conflict resolution concepts and techniques combined with drama strategies to address cultural conflict in schools. The use of formal cross-age peer teaching emerged as a highly effective strategy in teaching students to manage a range of conflicts in schools, and especially in learning to deal with bullying. Operating as peer teachers also enabled a number of students in the study, with serious behaviour problems, to re-engage with their learning. The article therefore evaluates the effectiveness of peer teaching in both conflict management and student re-engagement.