The effectiveness of computer-assisted instruction is unproven. Objective: To evaluate the effectiveness of an online computerized dermatology module compared to traditional lecture–based teaching to medical students. Methods: Medical students were randomized to two groups. Group 1 of 37 students had access to a computer-based dermatology tutorial. Group 2 of 36 students attended a lecture on skin morphology, identical to the tutorial, given by a dermatology faculty member. The main outcome was the total number of correct answers on a multiple-choice morphologic terminology final examination. The mean number of questions answered correctly was 16.14 and 14.89 for group 1 and group 2, respectively. Results: Unpaired statistical t tests showed the difference in mean scores between the two groups to be 1.25 (95% confidence interval: −0.70 to 3.20, p value = .20). Limitations: The study was small, with a small amount of material, and was brief in duration. Conclusions: Within the limits of our study, computer-assisted instruction is at least as effective as traditional lecture teaching of dermatology morphology to medical students.