His best known works include:
reviews of the research on long - term effects; benefit - cost analyses of the Perry
Preschool and Abecedarian programs; randomized trials comparing alternative approaches to educating children including length of day, monolingual versus dual - language immersion, the Tools of the Mind curriculum; and, the series of State
Preschool Yearbooks providing annual state - by - state analyses of progress in
public pre-K.