GOTR is a physical activity-based PYD program using running as a platform to teach life skills and promote healthy behaviors. In this study, girls in GOTR were compared to girls in Sport and PE on survey measures of life skills transfer and social processes (peer and coach relatedness, coach autonomy support) at season’s end. Focus groups were also conducted with GOTR stakeholders (girls, coaches, caregivers, school personnel). Survey results revealed that girls in GOTR compared favorably to girls in Sport and PE on all life skills—managing emotions, resolving conflicts, helping others, and making intentional decisions—and to PE girls for all three social processes. GOTR girls’ scores on life skills transfer remained stable at a three-month retention assessment. All stakeholders shared corroborating evidence that girls learn positive social and emotional behaviors through participating in GOTR that generalize to school and home contexts. Findings provide strong evidence that Girls on the Run is effective in teaching skills and strategies that generalize to broader life domains. The processes explaining group differences on life skills transfer point to GOTR’s intentional curriculum of skill-building activities delivered by trained coaches using a caring, mastery, and supportive climate.