Preschool Programs Can Boost School Readiness

In an earlier post on the Durable effects of concentrated disadvantage on verbal ability among African-American children I reported some rather depressing, if excellent, research measuring the cognitive penalties children suffer along with, and likely as consequences of, serious disadvantage. There's some relevant good news in this short paper by Gormley, Phillips and Gayer. (Also available at the publications section of the site of the Crocus project.)

This time around the data reports that specific pre-school programs among pre-school children leads to significant gains in scores on tests that are regarded as good predictors of later school achievement. Two programs. both in Tulsa, Oklahoma, were studied - the Head Start Program, and the Oklahoma pre-K program. Each differ in how they work (the differences are briefly described in the paper) and Oklahoma was selected partly because:

The Oklahoma pre-K program has relatively high standards compared with those of other states and offers relatively high pay and benefits to well-qualified teachers. Every lead teacher must have a B.A. degree and must be certified in early-childhood education. Student teacher ratios of 10-to-1 and class sizes of 20 must be maintained. The Community Action Project (CAP) of Tulsa County, whose Head Start program serves the largest number of children in Tulsa, is eligible for state funding. Its teachers meet the same standards as their Tulsa Public Schools (TPS) counterparts and receive similar pay (p1723).

To avoid selection bias students who'd attended were compared with students about to attend the respective interventions. Variation in ages at start allowed the relationship between age and test scores either side of the age cut off for entrance to be estimated. The analysis also conditioned on indicators of poverty and race, and found program participation to be a more powerful predictor of success. The results are impressive. Here's another quotation:

The TPS pre-K program has sharply improved students’ cognitive development.
One way to capture this is to look at the effect sizes: 0.985 for letter-word identification, 0.743 for spelling, and 0.355 for applied problems. These effect sizes substantially exceed those reported for pre-K programs generally and are somewhat greater than those reported for five states with relatively high quality pre-K programs. The effects of the Tulsa Head Start program, though less spectacular, are also impressive: 0.514 for letter-word identification, 0.334 for spelling, and 0.369 for applied problems. These effect sizes exceed those reported for a national study of Head Start with random assignment of children.

Then take a look at the figure, converting the measured gains into monthly equivalents. These figures are, according to the paper, greater than those (not represented in the graph) occurring through maturation.

Cool. Well resourced educational programs with qualified instructors and good pupil-teacher ratios actually do some good. Also, they do good even with kids who we've got good reason to expect have been cognitively harmed by their environments. That's hardly surprising, but it's good to get a sensible measure of it, especially with all the flaky opinionated yelling that goes on over education.

As with the paper by Sampson, Sharkey and Raudenbush I referred to previously, a key feature of this research is the construction of a large enough sample, with appropriate differentiation within it, to extract meaningful data with statistical tools. The more social science like this we see the better.

Gormley Jr., W.T., Phillips, D., Gayer, T. (2008). THE EARLY YEARS: Preschool Programs Can Boost School Readiness. Science, 320(5884), 1723-1724. DOI: 10.1126/science.1156019