This "What Works Clearinghouse Procedures and Standards Handbook (Version 3.0)" provides a detailed description of the standards and procedures of the What Works Clearinghouse (WWC). The remaining chapters of this Handbook are organized to take the reader through the basic steps that the WWC uses to develop a review protocol, identify…

REL Appalachia conducted a systematic review of the research evidence on the effects of increased learning time. After screening more than 7,000 studies, REL Appalachia identified 30 that met the most rigorous standards for research. A review of those 30 studies found that increased learning time does not always produce positive results. However,…