Abstract Positive youth development (PYD) offers an optimistic framework to enhance adolescent development. Proposed PYD outcomes include initiative and agency (Larson, 2000), and positive values termed the Five Cs: confidence, competence, connection, caring, and character (Lerner R. M., Lerner, J., et al., 2005). Previous research indicates that PYD is fostered through extra-curricular activity (ECA) participation in organised, structured settings, including sport and music. The main aim of this research was to explore the association between, principally, adolescents' music participation and their character development. Study 1 measured the music and sport ECAs of 246 first year university students, and their motivations for participation. Results showed that character was predicted by sport involvement and the motivations for music participation. Study 2 investigated the character development and well-being of 470 first year university participants through measures of sport or music experiences, engagement, and personality. Findings revealed that sport and music ECA involvement generally were not strong predictors of character development. However, indices of engagement experienced in sport and music activities were significant predictors, particularly activity enjoyment, even when controlling for personality. Results are discussed with respect to the implications for music ECA participation and PYD. Key terms: Positive youth development, extracurricular activities, music, sport, engagement, enjoyment, flow, character, flourishing.