Whole-group teaching presents serious difficulties for instructional effectiveness, because it creates the problem of requiring one teacher to discriminate among the behaviors of 20-30 students. The problem is further exacerbated in inclusive settings where teachers must differentially arrange tasks and feedback to maximize engagement and the developmental appropriateness of the lesson. Classwide peer tutoring (CWPT) has been promoted as an inclusive strategy (Block, 1995), however there is little research supporting this strategy in physical education. The purpose of this study was to assess the effects of CWPT on the catching performance of students with and without autism as they participate in physical education. The study was conducted in a school which served children with autism as well as their typically developing peers, and where there was emphasis placed throughout the curriculum on using the typically developing students as peer models. Physical education was taught twice per week for 30 minutes. This study was conducted over 26 lessons. Participants were 2 typically developing kindergarten students and 2 kindergarten students with mild to moderate levels of autism selected from a class of 14 students (2 males and 2 females). An A-B-A-B single subject reversal design was used to examine the effects of CWPT on their performance of catching tasks. Two critical elements were specified for each task in the unit. The dependant variable consisted of the task described by the teacher and the presence or absence of the critical elements. Data are reported as the number of total trials and the number of correct trials in 2-minute episodes. Performance of the task was videotaped and coded and the graphic data was visually analyzed. Interobserver agreement was conducted on 37% of the observations with 95% agreement. Results indicate that in general, participants increased their performance (%) and performed more trials during the classwide peer tutoring phase than during the whole group instruction phase. Though few trials were correctly performed during whole group instruction there was a small increase in the number of correct trials during CWPT. There are few studies in physical education that validate inclusion practices, and fewer still that focus on participants with autism. Thus, this study represents an important contribution to the literature on inclusion in physical education. Future research should examine the effects of CWPT on students' performance in other motor skills in addition to examining how best to train tutors to work with students with autism.Keyword(s): adapted physical activity, elementary education, performance