Randomized experiments are often considered the strongest designs to study the impact of educational interventions. Perhaps the most prevalent class of designs used in large scale education experiments is the cluster randomized design in which entire schools are assigned to treatments. In cluster randomized trials (CRTs) that assign schools to…

This report collects the results of all available empirical studies using the best available scientific methods to measure how school vouchers affect academic outcomes for participants, and all available studies on how vouchers affect outcomes in public schools. Contrary to the widespread claim that vouchers do not benefit participants and hurt…

Over the past several decades, researchers, politicians, and corporate leaders have focused reform efforts on the size of educational contexts. Hundreds of billions of public and private dollars have been invested to reduce the size and scope of both classrooms and schools (Lee & Ready, 2007). Unlike many education reforms, these downsizing…

"Positive Action," a K-12 program, aims to promote character development, academic achievement, and social-emotional skills and to reduce disruptive and problem behavior. The program is based on the philosophy that you feel good about yourself when you think and do positive actions, and there is always a positive way to do everything.…