OBJECTIVE The aims of this study were to investigate the prevalence of sports injuries in school physical education (PE) and leisure-time sports among 1011 15- to 16-year-old adolescents in relation to physical activity, and to examine goal orientation. METHODS A survey was used with additional narrative descriptions. RESULTS There was a higher prevalence of injuries in leisure time (645/993 = 65%) than in PE (519/998 = 52%). Two groups with high PE injury rates were identified: a) highly active (258/998 = 26%) in both school PE and leisure-time sports and b) highly inactive (180/998 = 18%) in both contexts. There were no differences between girls and boys. Task-oriented adolescents were more prone to injury. CONCLUSIONS The high prevalence of injuries in PE appears to have two mechanisms: renewed inadequately recovered leisure-time injuries among highly active adolescents, and injuries among fragile inactive adolescents unfamiliar with exercise. PE educators of these two groups with different injury patterns have a considerable didactic challenge. Knowledge of inadequately recovered injuries and consideration of the high volume and intensity of early sport-specific training in children and adolescents are important parameters in the design of lesson plans for PE.