Health and Human Services has finally released the second installment of its series of studies on the persistence of Head Start effects. Its finding (see page xiv): virtually all academic effects disappear by the end of 1st grade.

There is only one positive statistically significant finding out of eleven academic outcomes measured, the size of that effect is minuscule by recognized standards (it’s half way between zero and what most social scientists consider “small”), and the confidence in the finding is low by recognized standards. (Many authors would categorize it as “insignificant” rather than “significant”