Forty-eight studies on computer based instruction (CBI) in the elementary schools were coded on 45 variables using meta-analytic techniques. Results of the synthesis indicated computer assisted instruction (CAI) raised outcome measures by .45 standard deviation units. This is interpreted to mean that students in CAI treatment groups performed on the 65th percentile of the control group distribution. Results indicated that younger and lower achieving students profit most from exposure to CAI. Drill and practice is most effective in raising student achievement scores. The effects of computer managed instruction are minimal. The computer functions best when the task to be learned is relatively simple paired association.Keywords: computer assisted instructioncomputer managed instructionevaluation

A meta-analysis of 43 studies of the effects of computer-based instruction (CBI) in secondary schools showed that CBI programs produce, on average, small but significant improvement in students' scores on achievement tests. Results of the synthesis indicate that computer-based instruction raised the average performance by .32 standard deviation units. Drill and practice programs appear to he relatively less effective with secondary students than tutoring programs which introduce new concepts.