Students in regular public schools equaled or outperformed private and charter school students on a national mathematics exam when factors such as socioeconomic status, race, and school location were taken into account, a study released last week has found.
The two University of Illinois researchers who wrote the report say that their findings challenge perceptions that private schools produce better outcomes than public schools and raise new questions in the ongoing debate about school reform and privatizing education.
“There’s this assumption that private or independent schools by nature will have a positive effect on achievement,” said Christopher Lubienski, an education professor at the University of Illinois at Urbana-Champaign and a co-author of the study. “But if you are a child in a classroom, the governance structure doesn’t matter to you.”
Using data from the 2003 National Assessment of Educational Progress, the researchers examined math test scores from 13,577 schools where 4th and 8th graders took the federally sponsored test. Though private school students overall had better scores, the study showed that public school students outperformed them once they were compared with their peers in private schools with similar backgrounds.
Specifically, the researchers found that 4th graders in public schools scored better than their counterparts at Roman Catholic schools by more than 7 points. (Researchers compared mean scores on the NAEP math exam, which was 235 on a 0-500 scale for 4th graders.)
The same 4th graders outscored their counterparts at conservative Christian schools by more than 11 points, although researchers said the sample size of such schools was small and should be viewed as “only suggestive of patterns that may exist in the entire population of such schools.” Lutheran-school students scored roughly 4 points lower.
The report calls the public school students’ scores “statistically significantly higher,” because 10 points is generally considered to represent one grade level’s difference. “This analysis makes it appear that there isn’t anything magical in private schools that leads to a significant difference in achievement,” Mr. Lubienski said.
Statistics vs. Parents
The study also found that 4th gradestudents in charter schools scored 4.4 points lower than students in traditional public schools.
One private education advocate, however, said the study used a complicated statistical analysis that would have little bearing on how parents decide where to send their children to school.
“School choice is made at the local level when parents look at School A or School B and ask, ‘Is this school a match for my child?’ ” said Joe McTighe, the executive director of the Council for American Private Education, a Germantown, Md.-based umbrella organization for the nation’s private and independent schools. “Parents are asking whether the school sets high standards, if classrooms are safe and orderly, and if teachers are caring and demanding.”
Mr. McTighe also said the data used in the study can be analyzed many different ways.
“When you look at the data as is without any fiddling, students in privates outperform those in publics by a wide margin,” he said.
Mr. Lubienski, who studies school choice issues, wrote the report with his wife, Sarah Theule Lubienski, also an education professor at the University of Illinois at Urbana-Champaign. The report builds on the couple’s earlier study that analyzed 2000 NAEP math scores from a smaller pool of 1,300 public and private schools.
A $100,000 grant from the U.S. Department of Education paid for the new, more extensive report.
Their results were posted last week on the Web site of the National Center for the Study of Privatization in Education, based at Teachers College, Columbia University. The center is a research group that studies a range of issues such as publicly funded vouchers for private schools and turning public schools over to private managers.
Mr. Lubienski said he and his wife do not favor public schools over private schools.
“We didn’t set out to prove that privates aren’t as good as public schools,” Mr. Lubienski said, noting that he and his wife have attended private schools. “I think what these results demand, at the very least, is for privatization advocates to explain how their methods change what’s really happening in the classroom.”