This policy brief discusses new evidence regarding the effectiveness of Head Start. Head Start is the largest federal early intervention and education program in the United States, serving almost one million children in 2015. It was created in 1965 to narrow the gap between disadvantaged and more privileged children as they entered kindergarten, by providing comprehensive programming in preschool to improve children’s school readiness.
Early studies of Head Start and other pre-school programs found large positive effects on both cognitive and non-cognitive skills. But the first randomized experimental study of Head Start (the Head Start Impact Study, or HSIS), conducted in 2002, indicated that the program produced smaller benefits that faded out quickly. Some have interpreted this as evidence that Head Start is ineffective. Several recent studies by Berkeley authors, however, have shown that HSIS data, when interpreted appropriately, indicated that the program has significant benefits. Some of these benefits are persistent. When compared to at-home care, rather than to attending a similar program, attending a Head Start center generates positive effects on children’s development. This implies that the social return to Head Start spending is larger than previous analyses of HSIS data suggested. Moreover, the small average effects of Head Start mask significant variation in its benefits across groups of children and across Head Start centers. These new analyses represent an important contribution to the question of under what circumstances and for whom does Head Start work best.