New estimates of the effects of public preschool

Tom Daula writes:

You blogged about Heckman and the two 1970s preschool studies a year ago here and here.

Apparently there are two papers on a long-term study of Tennessee’s preschool program. In case you had an independent interest in the topic, a summary of the most recent paper is here, and the paywalled paper is here.

The research paper, by Mark Lipsey, Dale Farran, and Kelley Durkin, concludes:

This study of the Tennessee Voluntary Pre-K Program (VPK) is the first randomized control trial of a state pre-k program.

Positive achievement effects at the end of pre-k reversed and began favoring the control children by 2nd and 3rd grade. . .

It’s a long paper and I have not read it in detail so I won’t attempt to evaluate this empirical claim. At first it might sound surprising that preschool did not show positive effects, but the authors in section 6 of their paper do give some reasons why this might be the case.