Burton, Priscilla J.2017-03-022017-03-021961https://scholarworks.montana.edu/handle/1/11524The main purpose of this study was to investigate whether or not a form of ability grouping known as performance grouping had an effect on the students' achievement test scores that would not be obtained in a heterogeneous classroom. The major hypothesis held was that added gains would be shown on the standardized achievement test scores by the students in a school using performance grouping that would not be shown by students in a school using heterogeneous grouping.enAbility grouping in educationAcademic achievementMiddle school studentsA comparison of the achievement test scores in the intermediate grades in a school using performance grouping and a school using heterogeneous groupingProfessional PaperCopyright 1961 by Priscilla J. Burton