Over the past 15 years, we have seen an increase in the use of cluster randomized trials (CRTs) to test the efficacy of educational interventions. These studies are often designed with the goal of determining whether a program works, or answering the what works question. Recently, the goals of these studies expanded to include for whom and under…

Cluster randomized experiments are now widely used to examine intervention effects in prevention science. It is meaningful to use empirical benchmarks for interpreting effect size in prevention science. The effect size (i.e., the standardized mean difference, calculated by the difference of the means between the treatment and control groups,…

This group randomized controlled trial (RCT) evaluated the efficacy of Incredible Years Teacher Classroom Management Program (IY TCM) on student social behavioral and academic outcomes among a large diverse sample of students within an urban context. Participants included 105 teachers and 1817 students in kindergarten to third grade. Three-level…

A significant number of children in schools have mental health problems (World Health Organization, 2004). If children receive any type of mental health services, the vast majority receive these supports at school (Rones & Hoagwood, 2000). Mental health needs in children often manifest as emotional dysregulation, social incompetence, and…

In 2009, Vanderbilt University's Peabody Research Institute, with the assistance of the Tennessee Department of Education's Division of Curriculum and Instruction, initiated a rigorous, independent evaluation of the state's Voluntary Prekindergarten program (TN- VPK). TN-VPK is a full-day prekindergarten program for four-year-old children expected…