The purpose of this study was to investigate the effectiveness of a school-based physical education progressive resistance-training program on muscular strength, endurance, and work productivity of high school participants with mental retardation. Fourteen high-school participants matched according to age, gender, height, and weight were randomly placed into treatment and control groups. Treatment groups participated in a progressive resistance-training program and the control group participated in group and individual games. Both programs were 10 weeks in duration at a frequency of twice per week. Vocational and strength assessments were collected at three intervals five weeks apart plus a retention assessment. Peak isometric strength was assessed bilaterally using a hand-held dynamometer at the following sites: elbow flexion, elbow extension, shoulder abduction, knee flexion and knee extension, which were summed to create composite scores for the upper and lower body. Vocational assessments were representative of typical job skills for this population and consisted of a dolly push (timed distance), pail carry (timed distance), box stacking (timed repetitions), and chair stacking (timed repetitions). After termination of the treatment intervention at 10 weeks a retention assessment was administered 5 weeks after cessation of training. Based on a randomized complete block with repeated measures research design, a significant difference was found for all vocational tasks (chair stacking, F 1,6=9.79, p=.010; pail carry, F 1,6=4.65, p=.037; dolly push F 1,6=4.89, p=.018; & box stacking F 1,6=4.85, p=.035) with resistance training participants displaying higher mean scores than participants in control groups. In addition, percentage change data for isometric strength composites with treatment groups increased an average of 38.35% while the control group increased 4.08%. Based on the retention data mean percentage change for all participants in the training group decreased towards initial levels of functioning with isometric strength composites decreasing 11.42% and vocational tasks decreasing 12.64%. Based on the data analysis it was concluded that the school-based physical education training program was effective in increasing physical functioning and work-related skills, which can facilitate the school to work transition process.