Div. 7 award winners

Early Career Outstanding Paper Award winner: Arya Ansari

A summary of Arya Ansari's research, “Classroom Age Composition and the School Readiness of 3- and 4-year-olds in the Head Start Program.”

By Arya Ansari

There has been growing interest in publicly funded early care and education programs as a means of reducing socioeconomic and racial-ethnic disparities in children's early learning before the start of formal schooling. Part of this effort has included the expansion of preschool education to include not only 4-year-olds but 3-year-olds as well. Despite the fact that mixed-age classrooms represent one of the most common models of education in early childhood programs across the country, their efficacy in facilitating the early learning and development of young children has long been debated, with limited and dated empirical support. In fact, until our study, there had not been a national analysis of classroom age composition in the Head Start program, which is the nation's largest federally funded preschool program and which often serves both 3- and 4-year-olds in the same classrooms.

In this article (Ansari, Purtell, & Gershoff, 2016), which was published in Psychological Science, my colleagues and I examined the implications of classroom age composition in the Head Start program for low-income children's early academic and socioemotional development. To this end, we addressed the following two research questions. First, we examined whether classroom age composition was associated with 3- and 4-year-olds' early academic and social-behavioral development over the course of one preschool year. Then, we examined whether there were specific thresholds at which the associations between classroom age composition and children's early learning were either stronger or weaker.

We used a nationally representative sample from the Family and Child Experiences Survey 2009 Cohort to examine the experiences of newly enrolled 3- ( n = 1,644) and 4-year-olds ( n = 1,185) Head Start children from all 50 states and the District of Columbia during the 2009-10 school year. Roughly three out of every four Head Start children (77 percent) were enrolled in a mixed-age classroom that served both 3- and 4-year-olds.

Results from our investigation revealed that 4-year-old children in the Head Start program demonstrated fewer gains in mathematics and language and literacy skills during the preschool year when they were enrolled in classrooms with a greater number of 3-year-olds. When only 20 percent of their classmates were 3 years old, 4-year-olds demonstrated significantly smaller academic skill gains, equivalent to one month of learning. When as many as 45 percent of their peers were aged 3, these lost opportunities amounted to roughly four-to-five months of academic learning. In contrast to the experiences of 4-year-olds, classroom age composition was not consistently associated with the early academic or socioemotional development of 3-year-olds.

When taken together, the results from our study provided insight into the potential ramifications of classroom age composition in the Head Start program. Our findings that 4-year-old children made fewer academic skill gains and 3-year-old children were no better off in mixed-age classrooms indicate that we need to pay closer attention to the implementation of mixed-age classrooms in preschool settings.


Ansari, A., Purtell, K., & Gershoff, E. (2016). Classroom age composition and the school readiness of 3- and 4-year-olds in the Head Start program. Psychological Science, 27 (1), 53-63.