Weird Educational Science

Instapundit links to a study reported in the journal ScienceDirect which examined the short- and long-term effects of pre-kindergarten programs for disadvantaged children in Tennessee. Let's be charitable and call the findings counterintuitive, those who care about the wise expenditures of tax revenues might call them calamitous. The authors' summary includes this line:

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

I'm thinking assignment to treatment and control groups was not as random as the authors ask us to believe. Well-meaning, kind-hearted individuals making the assignments very likely selected for pre-K the children from the most dysfunctional backgrounds believing "they needed and could benefit from it more."

In the short run the pre-K kids benefitted. In the longer run the treatment group kids' troubled backgrounds proved more influential than their experiences in pre-K.

Much evidence shows kids from screwed up families are highly likely to be screwed up themselves, regardless of what the schools try to do. Everyone of good will wishes this wasn't so, but our wishing has proven ineffectual in producing positive results or changing negative outcomes.