Organized leisure activities are an important component of learning with a great potential for positive youth development. The available research has grown in the past decade but is still lacking differentiated analysis of specific activity determinants and longitudinal designs. Based on retrospectively collected quantitative data (n=1,547) at the end of low/middle secondary schools in Germany (9th/10th grades), this study explores patterns of organized activity participation over the school years using LCA (Latent Class Analysis). Four latent classes could be identified on the basis of eight manifest activity determinants: "None-Actives," "Minor-Actives," "Multiple-Actives," and "Committed-Actives." Sociodemographic indicators as well as social, cultural, and economic capital predict the assignment to these classes.