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.…

Using a unique dataset, this dissertation analyzes the relationship between observable teacher characteristics and teacher effectiveness. Effectiveness is measured as a teacher's ability to improve student achievement on a standardized test. This analysis focuses on teachers of math and science at the elementary and middle school levels, as well…