Delivering his first major address on education in March 2009, President Barack Obama promised the Hispanic Chamber of Commerce: “Secretary Duncan will use only one test when deciding what ideas to support with your precious tax dollars: It’s not whether an idea is liberal or conservative, but whether it works.”

Supposedly keeping with this commitment to “evidence based” policy, former Director of the Office of Management and Budget Peter Orszag made the case expanded Head Start funding in a recent edition of Annals of the American Academy of Political and Social Science. Problem is, as Heritage Foundation Research Fellow David Muhlhausen points out, the science just doesn’t say what Orzag says it does:

Orszag cites the 2010 Head Start Impact Study as evidence that the number of children participating in Head Start needs to be expanded. While the study experienced unusual delays in being released by Department of Health and Human Services, one would still naturally presume that the study found the program to be highly effective and, thus, deserving of expansion. … Overall, the program had little to no positive effects for children granted access to Head Start. For the four-year-old group, compared to similarly situated children not allowed access to Head Start, access to the program failed to raise the cognitive abilities of Head Start participants on 41 measures. Specifically, the language skills, literacy, math skills, and school performance of the participating children failed to improve.

Alarmingly, access to Head Start for the three-year-old group actually had a harmful effect on the teacher-assessed math ability of these children once they entered kindergarten. Teachers reported that non-participating children were more prepared in math skills than those children who participated in Head Start.

Also, Head Start has little to no effect on the other socio-emotional, health, and parenting outcomes of children participating in the program. For the four-year-old group, access to Head Start failed to have an effect for 70 out of 71 socio-emotional, health, and parenting outcomes. The three-year-old group did slightly better: Access to Head Start failed to have an effect for 66 of the 71 socio-emotional, health, and parenting outcomes.

In no way does the 2010 Head Start Impact Study demonstrate “very strong suggestive evidence” that Head Start “pay[s] off over the medium and long term.”[11] Placing more children into an already failed program does not represent placing “significant emphasis on making policy conclusions based on what the evidence suggests.”

We are sure that Orzag and President Obama have nothing but the very best of intentions when they promote Head Start expansion. And we are sure they believe that the very best social science evidence should show that Head Start works. But it doesn’t. As President Ronald Reagan once said: “The trouble with our liberal friends is not that they’re ignorant; it’s just that they know so much that isn’t so.”