Meta-Analyses of School and Instructional Effectiveness

Abstract

A meta-analysis was carried out on the basis of 155 research studies on school effectiveness, comprising a total of 1.211 associations between school effectiveness-enhancing factors and student outcome variables (replications). The original studies were carried out between 1984 and 2005. Next a meta-analysis on instructional effectiveness was carried out, based on 177 studies and comprising a total of 1912 replications, for which the original studies were carried out between 1990 and 2005. Results of the meta-analysis on school factors showed that effect sizes for the curriculum-related factors were relatively the highest (0.15), closely followed by the school climate factors (orderly climate and achievement orientation (0.14). According to widely accepted standards (Cohen in Statistical power analysis for the behavioral sciences. Academic Press, New York, 1969), these effects are to be considered as small effects; although in the discussion some arguments are provided that might lead to an upgrading of what one could call the “practical significance” of these effect sizes. The overriding conclusion of the meta-analysis of teaching factors is that effective teaching is a matter of clear structuring and challenging presentation and a supportive climate and metacognitive training. The results indicate that these main orientations to teaching are all important, and that effective teaching is not dependent on a singular strategy or approach. When comparing the effect sizes of the school-level factors to the teaching factors, the latter were slightly higher, on average: the average effect size of the school variables was about r = 0.08, whereas the average effect size for the teaching variables was about r = 0.10.