A study was conducted to determine the instructional effectiveness of supplementary computer assisted instruction (CAI) for high school equivalency training in the military. Thirty-two students in language arts classes and 32 students in mathematics classes were randomly divided into two groups: one receiving traditional instruction and the other traditional instruction supplemented by CAI. Students were Army enlisted personnel, none of whom were high school graduates. A CAI curriculum specifically tailored to the needs of the study was developed from existing lessons in language arts and mathematics available on the University of Illinois PLATO system. Students in the traditional group received instruction concurrently in the same topics as the traditional with CAI group. On all measures, scores for students in the traditional with CAI group were higher than for students in the traditional only group. The research indicated that CAI can successfully be implemented at an Army education center for use with students in the lower abilities range. (CMV)