Background: Peer-assisted learning (PAL) is a teaching strategy utilised in both the general classroom and physical education. Through the interaction with same-age or cross-age peers, learning can occur across various domains. Purpose: This review aimed to identify school-based PAL interventions and assess the tutor training provided, as well as the capacity of interventions to influence skill performance, physical activity and physical education participation, health and nutrition behaviours and anthropometric outcomes. Data Collection: A systematic review of databases yielded 19 papers reporting PAL in school physical education, sport or physical activity programmes. Results: Only four randomised controlled trials were identified in this review and only two other studies had control groups. Nine of the 19 studies reported significant findings; the implementation of PAL in a range of different physical education and physical activity contexts led to a diverse range of outcomes. Tutor training varied considerably; 13 of the 19 studies provided some training. Conclusions: Despite support for and success of PAL in other subject areas within schools, there have been few interventions implemented and vigorously evaluated within school physical education, sport or physical activity programmes. There is a need for future research to consider the duration and quality of tutor training in addition to measuring outcomes for both the tutee and tutor. Importantly, the adaptability of PAL across a range of settings provides scope for future research to assess its ability to impact on children and adolescents within a range of healthy lifestyle interventions both inside and outside the school environment.