Public schools equal or better in math than private or charter schools

Jan 24, 2006

Contrary to common wisdom, public schools score higher in math than private ones, when differences in student backgrounds are taken into account.

That was the conclusion of researchers Sarah and Christopher Lubienski in a study last year of data from the 2000 National Assessment of Educational Progress (NAEP).

Now they’re back with similar and more-extensive results in a follow-up study of the 2003 assessment, drawing from a much larger national data sample of 13,577 schools and 343,000 students.

The results, the researchers said, raise further questions about the assumed academic benefits of private, as well as charter, schools. The results also raise doubts about how effectively parental choice can influence school quality.

“The presumed panacea of private-style organizational models – the private-school advantage – is not supported by this (NAEP’s) comprehensive dataset on mathematics achievement,” the Lubienskis, education professors at the University of Illinois at Urbana-Champaign, wrote in a summary of their recent study.

A paper on the study was posted today (Jan. 23) on the Web site of the National Center for the Study of Privatization in Education (NCSPE), based at Columbia University. The study was funded through a $100,000 grant from the Institute of Education Sciences in the U.S. Department of Education.

“More and more states are looking at voucher programs, or trying to organize public schools on a private-school model, and this study brings up serious questions about that approach,” Chris Lubienski said. “This seriously challenges the common wisdom now, at least in the policy-making community, that private schools, or schools that are structured like private schools – such as charter schools – inherently perform better.”

The researchers looked at achievement and survey data from NAEP’s 2003 national sample of 190,000 fourth-graders in 7,485 schools and 153,000 eighth-graders in 6,092 schools. The schools in the sample were categorized by NAEP as public (non-charter), charter and private, with the private schools broken down further by Catholic, Lutheran, conservative Christian and “other private.”

NAEP is considered the only nationally representative ongoing assessment of U.S. academic achievement, and is often referred to as the “gold standard” of school performance data.

NAEP tests for more than just math, but the researchers chose to analyze math achievement because, unlike literacy, it is viewed as being less dependent on a student’s home environment and more an indication of a school’s effectiveness, Sarah Lubienski said.

As in the previous study, the researchers found what everyone expects when looking just at test scores: Private schools did better than regular (non-charter) publics. “Private schools are always going to do better if you’re not controlling for demographic differences,” Sarah Lubienski said.

Charter schools scored lower than regular publics in the fourth-grade sample, when looking just at test scores, and about even with regular publics in the eighth grade.

However, when they compared schools with similar student populations, based on students’ backgrounds – a kind of apples-to-apples demographic comparison – the private schools’ advantage disappeared, and even reversed in most cases.

Using a statistical analysis known as hierarchical linear modeling, the Lubienskis found that regular public schools scored “statistically significantly higher” than private and charter schools at the fourth-grade level. With 10 points roughly considered a grade-level difference in achievement, the regular public schools were trailed by 11.9 points by conservative Christian schools, 7.2 points by Catholic schools, 4.2 points by Lutheran schools, 5.6 points by all other private schools, and 4.4 points by charter schools.

At the eighth-grade level, the regular public schools were trailed by 10.6 points by conservative Christian schools and by 3.8 points by Catholic schools.

Lutheran and charter schools led regular public schools by 1.0 and 2.5 points, respectively, and all other private schools were 2.3 points below regular public schools – but all of these three gaps were determined to be statistically insignificant by the researchers.

To determine differences in students’ backgrounds, the researchers used NAEP survey data related to the students’ socioeconomic status, which included their eligibility for free or reduced lunch and their access to learning resources in the home, such as books and a computer. The researchers also incorporated survey data on students’ race and ethnicity; gender; disability and limited English proficiency.

The Lubienskis thought the gaps between regular public schools and conservative Christian schools were especially significant for any discussion about school choice. “Assumptions that academic quality will be driven by parental choice need to be re-examined in view of the fact that conservative Christian schools, the fastest growing segment of the private school market, were also the lowest performing,” they wrote in their summary of the research.

The researchers, who are husband and wife, caution that their conclusions are directed at policymakers rather than parents. They are not telling parents that the local public school is automatically better, any more than the common wisdom should tell parents that a local private or charter school is best. “We could imagine sending our kids to a private school if the circumstances were right,” Chris Lubienski said.

They also noted that the NAEP samples for some school types were limited, and cautioned against seeing their research as the last word on the subject. “We don’t think this is the definitive answer on this issue, but I do hope that it would put the brakes on – at least in people’s minds – about this rush to privately run schools,” Chris Lubienski said.

Source: University of Illinois at Urbana-Champaign

Explore further: Cougars' diverse diet helped them survive the Pleistocene mass extinction

add to favorites email to friend print save as pdf

Related Stories

Microsoft expands ad-free Bing search for schools

4 hours ago

Microsoft is expanding a program that gives schools the ability to prevent ads from appearing in search results when they use its Bing search engine. The program, launched in a pilot program earlier this year, is now available ...

Recommended for you

Not just the poor live hand-to-mouth

12 hours ago

When the economy hits the skids, government stimulus checks to the poor sometimes follow. Stimulus programs—such as those in 2001, 2008 and 2009—are designed to boost the economy quickly by getting cash ...

Math modeling handbook now available

14 hours ago

Math comes in handy for answering questions about a variety of topics, from calculating the cost-effectiveness of fuel sources and determining the best regions to build high-speed rail to predicting the spread ...

Archaeologists, tribe clash over Native remains

15 hours ago

Archaeologists and Native Americans are clashing over Indian remains and artifacts that were excavated during a construction project in the San Francisco Bay Area, but then reburied at an undisclosed location.

Male-biased tweeting

17 hours ago

Today women take an active part in public life. Without a doubt, they also converse with other women. In fact, they even talk to each other about other things besides men. As banal as it sounds, this is far ...

User comments : 0

More news stories

Male-biased tweeting

Today women take an active part in public life. Without a doubt, they also converse with other women. In fact, they even talk to each other about other things besides men. As banal as it sounds, this is far ...

Not just the poor live hand-to-mouth

When the economy hits the skids, government stimulus checks to the poor sometimes follow. Stimulus programs—such as those in 2001, 2008 and 2009—are designed to boost the economy quickly by getting cash ...

Archaeologists, tribe clash over Native remains

Archaeologists and Native Americans are clashing over Indian remains and artifacts that were excavated during a construction project in the San Francisco Bay Area, but then reburied at an undisclosed location.

FDA proposes first regulations for e-cigarettes

The federal government wants to prohibit sales of electronic cigarettes to minors and require approval for new products and health warning labels under regulations being proposed by the Food and Drug Administration.

Brazil enacts Internet 'Bill of Rights'

Brazil's president signed into law on Wednesday a "Bill of Rights" for the digital age that aims to protect online privacy and promote the Internet as a public utility by barring telecommunications companies ...

Vermont moves toward labeling of GMO foods

Vermont lawmakers have passed the country's first state bill to require the labeling of genetically modified foods as such, setting up a war between the behemoth U.S. food industry and an American public that overwhelmingly ...