Physical activity (PA) contributes to health throughout life. In particular, young people can benefit from this. Schools can play a key role in providing learning conditions to experience meaningful PAs aimed at inspiring students to lifelong PA. In this article, we argue the need for a salutogenic approach in schools focussing on respecting and enhancing adolescents’ agency with regard to their PA. This approach entails listening to adolescents’ perspectives and inviting them to participate in actively designing and carrying out PA as a prerequisite for their inclusive engagement. We unpack the concept of agency by drawing on insights from the Capability Approach. This provides input for the integration of agency in health promoting schools and salutogenic approaches, to enhance PA-related agency. Finally, we outline a research agenda to, eventually, create opportunities for students in schools to expand their PA-related agency. Lay Summary Physical activity (PA) contributes to health throughout life. Schools can play a key role in fostering meaningful PA experiences to inspire students to lifelong PA. This requires schools to focus on students’ personal aspirations, providing them with the space to develop their autonomy and find opportunities to decide and act upon expanding their agency with respect to the physically active lifestyles they deem meaningful.