Raleigh

Upon the release of the latest findings from a long-running National Institute of Child Health and Human Development study of child care in the United States, most reporters and policymakers in North Carolina and across the country immediately zeroed in on the most controversial discovery: that participation in day care appears to correlate with behavior problems later in school.

Time to wage another round of the Mommy Wars, some thought.

For me, though, this finding was not the right subject for the headline. If you look at the underlying data, the day-care effect on child behavior may have been statistically significant, but in practical terms it was modest. It would be wrongheaded to cite the study as "proof" that today's chaotic public-school classrooms or overcrowded juvenile-justice system are the inevitable result of mothers choosing to work outside the home.

No, to my mind the policymaking implications of the new study were to be found elsewhere.

Beginning in the early 1990s with Gov. Jim Hunt's Smart Start initiative, North Carolina had adhered to the notion that "investing" in early-childhood programs could pay substantial returns in student achievement and other improvements later on.

Gov. Mike Easley's subsequent contribution to rhyme-time politics, More at Four, advanced the idea that targeting tax money to at-risk 4-year-olds would offer the best opportunity to make a meaningful difference.

The problem is that, contrary to the claims of both administrations, there was little empirical or theoretical justification for believing that preschool programs such as Smart Start and More at Four would, in fact, produce anything like the promised outcomes.

Yes, there were a couple of laboratory experiments that had yielded promising results for desperately poor children placed in expensive, carefully controlled day-care environments. But the sample sizes were relatively small. And it was never reasonable to believe that such laboratory findings could be replicated in large-scale programs funded and run by government agencies.

Indeed, early evidence from Smart Start and More at Four has suggested that whatever gains participating students exhibited compared with otherwise-similar non-participants, they were so small that, as in previous experience with Head Start, the gains were unlikely to persist past the second or third grade.

For the most part, the new NICHD study results confirm this unfortunate prediction. What researchers termed "high-quality day care" -- care by an engaged, responsive adult in a rich, nurturing setting -- did not lead to any lasting gains for fifth-graders in reading or mathematics.

On the other hand, the study did confirm the persistence of gains in vocabulary among fifth-graders who had gone through high-quality day care. But, as with the negative behavioral effects, the impact was modest.

Far too many policymakers have seen early-childhood intervention as a way for the government to inoculate disadvantaged students against the adverse effects of poverty, bad parenting, and shoddy schooling. It won't work. Parenting is by far the largest factor affecting student success.

There are alternative policies the offer a realistic prospect of much-larger gains than preschool intervention. For example, there is now enough solid research to conclude that certain teaching approaches work best to reduce achievement gaps.

There is also enough solid, experimental research to demonstrate that poor children, at least, benefit significantly from choice programs involving public and private schools.

Let's get cracking.

John Hood is president of the John Locke Foundation and publisher of CarolinaJournal.com.