This investigation focused on the effects of a treatment package including multiple exemplar training, time delay, and a self-directed learning prompt (KWHL chart) on students' ability to complete an inquiry lesson independently and generalize to untrained materials. Three middle school students with moderate intellectual disabilities learned to self-direct themselves through a 15-step task analysis to complete inquiry lessons in chemistry and physical science. All three students achieved mastery across materials, science concepts, and instructional settings, but unanticipated generalization weakened the demonstration of experimental control. The results provide a potential method for students with moderate intellectual disabilities to learn science concepts. (Contains 7 figures and 1 table.)