Abstract
Every year, teachers, principals, superintendents, and other educators have to make hundreds of decisions of potentially great importance to students. What reading program is most likely to ensure high reading performance? Should “social promotion” be used or should retentions be increased? Should summer school programs be provided to struggling students? Should kindergarten be half day or full day? What are the most effective means of providing remediation to children who are falling behind? In a word: What works?