Critiques the conclusions of S. Veenman (1995) about multigrade classes and suggests that selection bias and lower-quality instruction should be included as part of the explanation for his findings of no difference. Indicates that multigrade classes have at least a small negative effect on achievement and potentially negative effects on teacher…

D. Mason and R. Burns (1996) have concluded that multigrade classes have a slightly negative effect on students' achievement. However, a reanalysis, based on meta-analytic procedures, of the available studies shows the average weighted effect sizes to be essentially zero or close to zero. Contains 51 references. (SLD)

Using results of a best-evidence synthesis and a meta-analysis of an extensive international database, it is argued that there is no empirical evidence at the moment showing that student learning suffers in combination classes. No support is found for the selection bias suggested by D. Mason and R. Burns (1997). (SLD)

S. Veenman argues that his reviews of the literature lead to the conclusion that combination classes are neither worse nor better than single-grade classes. This rejoinder discusses disagreements with Veenman's findings, which are hampered by a narrow reading and interpretation of the literature on potential positive effects of combination…