We estimate the effects of relative age in kindergarten using data from an experiment where children of the same age were randomly assigned to different kindergarten classmates. We exploit the resulting experimental variation in relative age in conjunction with variation in expected kindergarten entry age based on birth date to account for…

The purpose of this study was to explore the differences between Reading/Language achievement gains of students in multi-age classrooms to the Reading/Language achievement gains of their peers in traditional, single-age classrooms. The causal-comparative quantitative approach to exploring cause-and-effect relationships was employed in this study.…