This dissertation examines the efficacy of peer tutor training in adapted physical education (APE). A peer tutor evaluation form was created to assess the skills of untrained peer tutors (n = 12). Once skills were assessed, a peer tutor training protocol was created. The protocol was implemented in a peer tutor training program. After peer tutors were trained, they participated in an APE peer tutor program for students with severe disabilities in elementary school (K-6). This study measured the effects of trained and untrained peer tutors on motor performance, number of steps. Peer tutor attitudes were also evaluated. The study employed a single-subject multiple baseline design with 24 participants (12 students with severe disabilities, 12 students from general population) in a public elementary school. The acquisition of motor skills was determined using the TGMD-2; exchange of verbal information was assessed using the peer tutor evaluation form, steps were counted for the entire class time using pedometers. Results of this study showed trained peer tutors had a positive effect on tutee motor skill acquisition as represented by statistically significant t-test results, and step counts as represented by level change in multiple baseline data. Peer tutor performance was also effected by training as illustrated by substantial level change and minimal overlap in multiple baseline data. Change in peer tutor attitude was also statistically significant as represented by a Wilcoxon signed rank test. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]