Ability Grouping in Elementary Schools: Do We Really Know Nothing Until We Know Everything?

In responses to “Ability Grouping and Student Achievement in Elementary Schools: A Best-Evidence Synthesis,” Elfrieda Hiebert and Adam Gamoran express concern that the review only compares alternate forms of ability grouping without documenting actual classroom practices. In this rejoinder, it is argued that while process data would also be valuable, such “A versus B” research is critical in informing researchers and practitioners, who must make “A versus B” decisions about grouping. Also addressed is the possibility that effects of the Joplin Plan may be due to novelty effects, to factors other than cross-age grouping, or to unique conditions of schools 20 years ago. While conceding that the ability grouping research reviewed is not perfect, the rejoinder argues that matched or randomized comparisons of effects of alternative grouping plans on standardized tests over periods of one or more semesters tell us much about the effects of ability grouping.