Many youth participate in extracurricular activities, and research has linked activity participation with school engagement and academic success. Social-ecological theory suggests that the social contexts of different types of extracurricular activities may differentially affect student outcomes. Yet, there is scant research examining the relation between various extracurricular activities and student outcomes. The current study seeks to address this gap by exploring how participation in three activities (sports, clubs, and arts), and combinations of these activities are associated with perceptions of school climate, using multilevel modelling. Participants included 15,004 high school students from 28 schools across 11 states in the United States. Findings suggest that students involved in extracurricular activities have more favourable perceptions of social-emotional security, adult support, student support, and school connectedness. However, these perceptions vary by activity type and combination, and do not appear to have a stacked effect in which involvement in more activities yields more favourable outcomes. We conclude that extracurricular activity participation may serve as a mechanism to promote a positive school climate. Implications for research and practice are discussed.