Via Joanne Jacobs: San Francisco Chronicle reports that Oklahoma and Georgia have seen no improvement on achievement test scores since implementing universal preschool programs. It also refers to a discouraging-sounding large-scale study of Tennessee’s preschool program, although it doesn’t give a specific citation (and I can’t find one online).

A couple things to keep in mind:

• All of the discouraging results cited here refer to achievement test scores. Possible impacts on mental health, later life outcomes, etc. are not discussed.
• The Tennessee finding is reported as excluding “at-risk kids.” We’ve always thought it very possible that early childhood care is most beneficial to at-risk children, and indeed that the gains for such children may account for the entire observed effects.

Our existing position on large-scale preschool programs is that no strong evidence exists for their effectiveness. The programs discussed here are unusually high-intensity programs, so the findings do call into question whether replicating the encouraging results of model programs is even theoretically possible.

Note that none of this discussion pertains directly to our current top charity in early childhood care, the Nurse-Family Partnership (our review here).