While most states require testing in social studies or civic education, two states attach consequences for students and schools based on required statewide civics exams. Lawmakers in Florida, in 2010, and in Tennessee, in 2012, approved legislation that holds students accountable for their civics knowledge. Students are taking the tests for the…

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.…