Developing competency in motor skill assessment has been identified as a critical need in physical educator preparation. We conducted this study to evaluate (a) the effectiveness of a web-based instructional program--Motor Skill Assessment Program (MSAP)--for developing assessment competency, and specifically (b) whether competency developed by using this method transferred to participants' ability to accurately assess actual students in a gymnasium setting. Participants were 36 (9 men and 27 women) preservice kinesiology majors. Results revealed they performed significantly better on assessing a motor skill after using MSAP training, and this training transferred to significant improvements in accurately assessing students in an actual gymnasium setting. (Contains 3 figures.)