Disaggregating the Between-Person and Within-Person Associations Between Peer Acceptance and Academic Achievement in Early Elementary School.

We examined the between-person and within-person associations between peer acceptance and academic achievement in early elementary school years. Drawing on a sample of 784 academically at-risk students, the random intercept cross-lagged panel model was implemented to disaggregate the between- and within-person associations between peer acceptance and academic achievement from Grades 1 to 3. Academic achievement was measured using standardized achievement tests and teacher reports. Peer acceptance was measured using sociometric ratings. Positive associations between peer acceptance and academic achievement were found at the between-person level. At the within-person level, peer acceptance was not associated with standardized achievement test scores, and it was negatively predicted by teacher-reported academic achievement. These findings reveal the heterogeneous associations between peer relation and academic achievement at different levels of analyses and highlight the importance of disaggregating the between- and within-person associations for a better understanding of the nature of this developmental relation.