The nested data structure inherent in education (i.e. students nested in schools nested in districts) makes intact school matching an appealing approach in observational studies of educational interventions and policies for both theoretical and practical purposes. This paper provides guidance to applied education researchers who are employing…

Teachers spend most of their time in school in classrooms, and their instruction and teaching practices may be affected by classroom context such as class size. We examine whether teacher effects interact with classroom context such as class size. Specifically, we seek to determine whether teacher effects are more pronounced in small classes than…

Over the past several years, states have come under increased pressure to improve the academic achievement of all students in their schools. As states have looked for ways to accomplish this task, more and more have turned to class size reduction, particularly in the early elementary grades. In this paper, we summarize evidence from two…

In recent years, propensity score matching (PSM) has gained attention as a potential method for estimating the impact of public policy programs in the absence of experimental evaluations. In this study, we evaluate the usefulness of PSM for estimating the impact of a program change in an educational context (Tennessee's Student Teacher Achievement…

Effects of class size on academic achievement were studied for 2 years using 6,572 kindergartners in Tennessee assigned to large classes (22 to 25 students) or small classes (13 to 17 students). Significant benefits of small class size were seen in reading and mathematics achievement, especially for minority students. (SLD)

In this study we test the performance of some nonexperimental estimators of impacts applied to an educational intervention--reduction in class size--where achievement test scores were the outcome. We compare the nonexperimental estimates of the impacts to "true impact" estimates provided by a random-assignment design used to assess the…

This report presents results of Tennessee's 4-year longitudinal class size project: Student Teacher Achievement Ratio (STAR). The study analyzes student achievement and development in three class types: small classes with 13-17 students per teacher; regular classes with 22-25 students per teacher, and regular classes with 22-25 students per…