[A]s the evidence has built up, Head Start is failing its test. The latest evidence appears in the “Third Grade Follow-up to the Head Start Impact Study: Final Report,” which was released in December. The report was carried out by a company called Westat and published by the Office of Planning, Research and Evaluation, Administration for Children and Families, U.S. Department of Health and Human Services. Basically, the report shows that Head Start provides short-term gains to preschool children, but those gains have faded to essentially nothing by third grade.

To appreciate how depressing this conclusion is, you need to appreciate the high quality of the study. It’s based on a nationally representative sample of more than 5,000 3 and 4 year-olds from low-income families who were eligible for Head Start. These children were randomly either assigned to Head Start, or not. Data collection started in 2002, and so by 2008, data was available on how the children were performing in third grade. The study didn’t just look at test scores: it considered a range of data on how Head Start might affect aspects of cognitive development, social-emotional development, health status and services, and even parenting practices.

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