One hundred eighty studies of science inservice projects reported in the literature from 1973-1980 were reviewed. Sixteen of these studies contained sufficient data for meta-analysis (technique by which treatment effects can be quantified, standardized, and compared using a "size effect" statistic). The magnitude of the effect of the science inservice on teachers and/or their students was considered for this particular analysis. A total of 59 effect sizes was obtained from the 16 studies and grouped into subsets of teacher knowledge, teacher attitude, students knowledge, student attitude, implementation-use of National Science Foundation (NSF) curricula, and preferred type of inservice programs for further analyses. The overall average effect size for science inservice projects, regardless of emphasis, was + .84. The results suggest that science inservice projects have had considerable effect on teachers and/or their students. (Author/DC)