In a study sponsored by the Institute of Education Sciences, intensive professional development programs for seventh-grade math teachers were implemented as intended, but teacher turnover limited the average dosage received. The programs had no impact on teacher knowledge or student achievement.
This paper provides practical guidance for researchers who are designing and analyzing studies that randomize schools — which comprise three levels of clustering (students in classrooms in schools) — to measure intervention effects on student academic outcomes when information on the middle level (classrooms) is missing.
This paper illustrates how to design an experimental sample for measuring the effects of educational programs when whole schools are randomized to a program and control group. It addresses such issues as what number of schools should be randomized, how many students per school are needed, and what is the best mix of program and control schools.