Background: Cluster-randomized experiments that assign intact groups such as schools or school districts to treatment conditions are increasingly common in educational research. Such experiments are inherently multilevel designs whose sensitivity (statistical power and precision of estimates) depends on the variance decomposition across levels.…

Achieve was asked by the Washington State Academic Achievement and Accountability Commission, Office of the Superintendent for Public Instruction, and the Partnership for Learning to conduct a study of the 10th grade Washington Assessment of Student Learning (WASL). The intent of the study was to compare the content, rigor and passing scores on…