Classmate Turnover and Student Achievement: New Findings from Project STAR

Marc Luppino, Federal Trade Commission (FTC)

New classroom assignment at the onset of each grade means that a student's peer group regularly changes over an academic career. This is one of the first papers to examine how peer turnover impacts student outcomes. I use the random variation in classroom composition induced by Tennessee's Student Teacher Achievement Ratio (STAR) experiment to identify the causal effect of classmate turnover on academic achievement. In schools outside of center cities, I find that first graders who experience greater classmate turnover perform worse in reading and math. Conversely, peer turnover is found to be beneficial for young students in center city schools. These results are consistent with a model of classroom learning in which familiar classmates can either be a resource or a distraction. They suggest that a richer understanding of peer continuity effects is essential for designing optimal classroom assignment policies.