Group workers frequently use standardized skill-building curricula to teach elementaryaged children prosocial ways of interacting with peers. The findings of this study of group sessions of an urban violence prevention project indicate that there are challenges to this process. Leaders must manage the behavior of young children, develop a cohesive group, and allow adequate time for full delivery of skills that are age and culture specific. Training for this method of skill building must include knowledge of behavioral reinforcement and group dynamics and support for balancing curricular content with the specific concerns of group members.