private school advantage disappears

Apples and oranges happen to be among my favorite things at the long end of the color spectrum, so I'm always happy when people analogize around them. As a Texan in Philadelphia, I've become adept at fitting square pegs into round holes. Through a career in the nonprofit world, I've even learned how to get blood from a stone. But make a statistically-based comparison between public and private school? Now that gift has long eluded me.

Along comes today's New York Times, which reports, in Public-School Students Score Well in Math in Large-Scale Government Study , the results of a study of public, charter, and private school students on a 2003 standardized test, the National Assessment of Educational Progress. The researchers compared NEAP results of 340,000 students in fourth and eighth grades.

Not that I'm distrustful of the Times, but why read an article about the study when I can read the study? It's like reading a review of a movie but not seeing the movie. What if it's really good afterall?

So, direct from
Charter, Private, Public Schools and Academic Achievement: New Evidence from NAEP Mathematics Data,
by Christopher Lubienski and Sarah Theule Lubienski, at The University of Illinois:

(you ready for this?)

"Without controlling for student background differences, private schools scored higher than noncharter public schools, as would be expected. However, this study examines these patterns further, determining whether they are due simply to the fact that higher proportions of disadvantaged students are enrolled in public schools, and the extent to which the gaps persist after controlling for potential student- and school-level confounding variables, including measures of socioeconomic status, race/ethnicity, gender, disability, limited English proficiency, and school location.

"Overall, the study demonstrates that demographic differences between students in public and private schools more than account for the relatively high raw scores of private schools. Indeed, after controlling for these differences, the presumably advantageous 'private school effect' disappears, and even reverses in most cases."

Explore the US Department of Ed's "Nation's Report Card.