This study was conducted to identify student characteristics and instructional factors that impact student engagement in physical education (PE). Data were derived from the systematic observation of 124 sessions taught by 31 physical educators and the administration of health and PE engagement questionnaires to 2,018 students in grades 5-8. Physical activity was directly affected by student engagement and perceived competence in PE and indirectly affected by students' body image through its association with PE engagement. Multilevel analyses revealed that the proportion of class time devoted to game play was negatively associated with student engagement in PE. Although less frequently used during PE sessions, skill practice was positively associated with student engagement and inactive instruction was negatively associated with student engagement. These effects were particularly pronounced among students with poor competence beliefs. Implications for PE instructional practice and future research are presented. (Contains 3 tables and 3 figures.)