Using data from the Head Start Impact Study, this paper examines variation in Head Start effects across individual children, policy-relevant subgroups of children, and Head Start centers. It finds that past estimates of the average effect of Head Start programs mask a wide range of relative program effectiveness.
An Empirical Assessment Based on Four Recent Evaluations
This reference report, prepared for the National Center for Education Evaluation and Regional Assistance of the Institute of Education Sciences (IES), uses data from four recent IES-funded experimental design studies that measured student achievement using both state tests and a study-administered test.
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.