Involvement in social action and community service can promote the construction of prosocial identities and enduring patterns of civic behavior. This article explores this important process for youth that participate in the PeaceJam Ambassadors program. High school-aged "PeaceJammers" study the lives of Nobel Peace laureates while creating projects to affect change in their local communities. Multiple methods were used to access youth perceptions including surveys and interpretive interviews. Participants reported high levels on indicators on personal and social change. Their narratives articulated salient influences on their identities and actions. They shared how advisors promote social identity, participation, and the development of moral identities. These findings add to a growing empirical literature on moral development and youth engagement in peace education and community transformation.