This research study examined the effects of classwide peer support training on the occurrence of initiated and reciprocal peer interactions of students with significant disabilities in two inclusive physical education classes. An AB research design was used to document changes in the occurrence of initiated and reciprocal peer interactions of students with significant disabilities following the provision of peer support training to all of their classmates. Four students with significant disabilities were observed in the study and baseline and post-intervention data on the occurrence of peer interactions were collected. The peer support training was provided to classes where four students with significant disabilities were included (two students in each classroom). Thirty-seven peers in the physical education classes were taught to (a) identify expectations within a single activity designed for the entire class in which a student with significant disabilities could also participate, (b) utilize the concept of partial participation to meaningfully include a student with significant disabilities in physical education classroom activities, (c) address priority educational goals from a student's Individual Education Plan during group activities, (d) use positive feedback and reinforcement to encourage participation, (e) program and use augmentative communication devices for meaningful participation in activities occurring in a physical education classroom, and (f) employ strategies to facilitate the development of peer relations and encourage interactions in ways that provide alternatives to an overreliance on paraprofessionals. After the peer support training was provided to the students in both physical education classes, follow-up observations were conducted to determine the impact of that peer support training on the occurrence and type of peer interactions of students with significant disabilities in inclusive physical education classes. Increases in the occurrence of interactions, as well as increases in both initiated and reciprocal peer interactions were documented as additional opportunities for students with significant disabilities to interact with their classmates were created. With the total number of peer interactions increasing following the training for each of the four boys, the success of the strategies employed could lead to increased levels of acceptance and access to other areas of the general education environment alongside their peers without disabilities.