Do Preschool Peers Create a Sustaining Environment in Kindergarten? Evidence from the ECLS-K:2011

Using the Early Childhood Longitudinal Study - Kindergarten Cohort 2011, we examine (i) whether more preschool attendees in a kindergarten classroom relate to higher academic and social skills for children who did not go to preschool, (ii) whether more preschool attendees in the classroom moderate the benefits of preschool attendance (child N = 11,360; class N = 2,460; 67% White; 51% males; M _age = 5.6 years), and (iii) whether more preschool attendees in the classroom relate to teachers' perceptions of children's skills and their instructional content. In contrast to prior analyses using the 1998 cohort of the ECLS-K, we found no evidence of an association between the classroom percentage of preschool-attending peers and children's academic, executive function, and behavioral and prosocial skills. However, we found that the percentage of preschool peers was associated with teachers' perceptions of children's reading skills and teachers' instructional time spent on advanced reading content.