As I described last week, the Department of Health and Human Services has been sitting on an evaluation of the Head Start government run pre-school program. Well, today the study was released (and it’s not even a Friday!).
As the leaks suggested, the study found virtually no lasting effects to participation in Head Start. The study used a gold-standard, random assignment design and had a very large nationally representative sample. This was a well done study (even if it mysteriously took more than 3 years after data collection was complete to release the results).
For students who were randomly assigned to Head Start or not at the age of 4, the researchers collected 19 measures of cognitive impacts at the end of kindergarten and 22 measures when those students finished 1st grade. Of those 41 measures only 1 was significant and positive. The remaining 40 showed no statistically significant difference. The one significant effect was for receptive vocabulary, which showed no significant advantage for Head Start students after kindergarten but somehow re-emerged at the end of 1st grade.
The study used the more relaxed p< .1 standard for statistical significance, so we could have seen about 4 significant differences by chance alone and only saw 1. That positive effect had an effect size of .09, which is relatively modest.
For students randomly assigned to Head Start or not at the age of 3, the researchers also collected 41 measures of lasting cognitive effects. This time they found 2 statistically significant positive effects and 1 statistically significant negative effect. For the students who began at age 3 they showed a .08 effect size benefit from Head Start in oral comprehension after first grade and a .26 effect size benefit in spanish vocabulary after kindergarten but a .19 effect size decline in math ability at the end of kindergarten. Again, 38 of the 41 measures of lasting effects showed no difference and the few significant effects (which could be produced by chance) showed mixed results.
I think it is safe to say from this very rigorous evaluation that Head Start had no lasting effect on the academic preparation of students.
The study also measured lasting effects on student behavior and emotion as well as the skills of parents. Again, the effects were largely null and the few significant differences were in mixed directions. The few positive effects from these categories were from parent reports and the few negative tended to come from teacher reports.
The long and short of it is that the government has a giant and enormously expensive pre-school program that has made basically no difference for the students who participate in it. And folks are proposing that we expand government pre-school to include all students. Those same folks have some bridges they’d like to sell.
(edited for clarity)
Jay P. Greene's Blog 
As Private Hudson said in Aliens:
GAME OVER MAN! GAME OVER!!!
Yeah, but Hudson and something like four or five other people ended up surviving. My guess is Head Start will, too.
(Do not talk to me about what happened in the next movie!)
Hudson bit the dust. You are thinking of Hicks who survived, only to be written out of the awful third installment.
I also suspect Head Start will survive, but the intellectual debate over early childhood programs as an education reform strategy just suffered a fatal blow.
On second thought, it is more like pulling the plug.
I agree this is the death blow for the intellectual debate over p-k programs, but that will change little, as a practical matter, if no one knows about the study’s results. This news isn’t getting a fraction of the coverage it merits.
Yes, that’s right, he was defending Operations while the rest of the group climbed into the ventilation duct (the biggest darn ventilation duct you ever saw) and an alien came up out of the floor under his feet.
I hang my head in shame.
Thanks for the link to the study – verrrrry interesting reading. It will be interesting to see how this all plays out.
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