Abstract: This study employs a life-course approach to investigate the role of participation in school-based extracurricular activities as a compensatory source of social capital for adolescents, particularly those reared in non-traditional families and the effect of participation on early adult outcomes. Using Waves I and III from the Add Health data, four young adult outcomes are examined: high school completion, college attendance, civic involvement, and drug use. Findings illustrate that the protective effect of adolescent extracurricular activity participation is dependent on both the outcome in question and the activity itself. Interestingly, adolescent extracurricular activities are no more important for children from alternative family structures. However, benefits of participation are still evident from this examination, even when controlling for measures of social capital. Survey analysis techniques which control for the complex sampling design in Add Health are used.