An ergonomics awareness program developed for apprentice carpenters was evaluated. The program was developed for apprentice carpenters in the Cincinnati, Ohio area and was intended to increase their knowledge of carpenters' work related musculoskeletal disorders (WRMDs) and construction ergonomics, to enable them to identify potential WRMD risks, and to motivate them to act to prevent WMDs. The program included short lectures that covered the anatomic, physiological, and biomedical characteristics of the back, neck, shoulder, hands and wrists, elbows, and knees; WRMDs that could affect these areas; specific WRMDs for carpenters; and strategies for preventing WRMDS, which were followed by hands/on activities that were integrated into small scale construction projects that were completed in a carpentry shop. The hands/on activities were designed to reinforce the classroom presentations and to allow the participants to apply their knowledge to evaluating tools and equipment designed to reduce musculoskeletal stress, complete carpentry tasks using different methods, and to perform ergonomic evaluations of selected job tasks. The total duration of the program was 16 hours. Eighteen of 37 carpenters that entered apprentice training in 1994 and 1995 participated in the program. The other 19 did not and served as controls. Both groups completed an identical series of four ergonomics based tests and a final comprehensive test. The group participating in the program also completed four class evaluations and a final program evaluation. The apprentices who participated in the program scored significantly higher on two of the four tests and the final comprehensive test than the controls. The program participants found information on cumulative trauma disorders (CTDS) associated with carpentry, ergonomic tool evaluation, and evaluating ergonomic hazards to be useful, and information on physiology and CTD risk factors 'highly useful'. They consistently preferred participatory teaching methods over the traditional classroom teaching format. Less than half found listening to lectures helpful or useful. The authors conclude that these results indicate that apprentice programs should provide regular 'learner centered' occupational safety and health education that includes ergonomics and that such programs should be integrated with the shop based training.