New Research Brings Good News About Charter Schools

Report Education

New Research Brings Good News About Charter Schools

December 14, 2004 4 min read

Authors: Jennifer Marshall and Kirk Johnson

Charter schools are succeeding in their mission to provide an educational alternative more likely to lead to student proficiency, according to a study released today by Harvard economist Caroline Hoxby. Across the nation, charter school students are more likely to be proficient in math and reading than students in the nearest comparable regular public school. In well-established charter schools, students' prospects of proficiency are even greater.


As publicly funded schools that operate outside the regular system, charter schools can employ innovative approaches to meet student needs. Hoxby's findings give good reason to be optimistic about charter schools' potential to improve educational opportunities in those areas most poorly served by regular public schools.


Findings from the Hoxby Study


Caroline Hoxby's study[1] shows that charter school students are more likely to be proficient in math and reading than students in the nearest comparable public school. Overall, charter students have proficiency rates that are 5.2 percent higher than their public school counterparts in reading and 3.2 percent higher in math.


Further, Hoxby's study shows that charter school students' gains in academic achievement, relative to their public-school counterparts, tend to increase as the charter schools mature. In other words, charter schools are pulling away from public schools in terms of performance. For example, children at charter schools that have been operating for 1 to 4 years are 2.5 percent more proficient in reading than students in the nearest comparable public school. That proficiency advantage increases to 5.2 percent for charter schools open 5 to 8 years, and to 10.1 percent for charter schools operating 9 to 11 years. This indicates that the full potential of charter schools may not be realized until after a number of years of operation.


This makes sense. Like other new schools, charter schools must contend with start-up issues like hiring teachers and administrators, selecting a curriculum, and securing facilities. Additionally, charter schools tend to attract the very students whom their previous public schools left behind. As Hoxby notes, "Affluent parents whose children are doing fine in suburban schools rarely send them to fledgling charter schools."


Many charter schools in minority and high-poverty areas show even greater achievement gains. For example, students of charter schools in Hispanic areas have a 7.6 percent advantage in reading, and charters in African-American areas have a 4.5 percent advantage, compared to a 4.2 percent advantage for students in charter schools in other areas.


Similarly, students at charters in high-poverty areas have a reading proficiency advantage of 6.5 percent, compared with a 2.6 percent advantage for students in other charter schools. This suggests that charter schools have the most promise in the areas that have the greatest need for innovative educational reforms.


The Hoxby Study in Context of the Current Debate

This study's results stand in stark contrast to another study of charter schools recently released by the American Federation of Teachers. The AFT study argued that fourth graders in charter schools lag fourth graders in traditional public schools in academic achievement. This AFT analysis, however, fails on a critical point.


Charter schools typically target disadvantaged populations. Well-heeled parents in higher-achieving locales are often content with the schools their children attend. Charter schools are most popular, however, where local public schools have failed their students. Therefore, comparing traditional public schools, which serve a broad student body, and charter schools, which typically serve targeted or disadvantaged populations, reveals no more than comparing apples to oranges.


The Hoxby study escapes this criticism. It compares individual charter schools with their nearest traditional public school counterparts, either in terms of geographic proximity or demographic characteristics. This matched public school would be most likely to educate the charter school's children in the absence of the charter school, making it the most logical basis for comparison.


While AFT boosters respond that the AFT study controlled for race, income, and geography, the Manhattan Institute's Jay P. Greene recently pointed out why this, too, falls short:


Focusing on superficial similarities doesn't overcome the fundamental differences. Because so many charter schools are specifically targeted to struggling students, a large percentage of their minority and poor students face obstacles greater than students of similar demographics in regular public schools. There's just no comparison.[2]


Put another way, the matched schools approach allows for a better-targeted analysis of charter schools in comparison to traditional public schools. The AFT study, on the other hand, employs a "shotgun approach" that conceals individual charter schools' great successes.



Caroline Hoxby has provided an important evaluation of charter schools. Her findings indicate that this entrepreneurial and innovative educational effort is reaping positive results, particularly for students ill-served by public schools. With the supply of charter school data now sufficient for robust analysis, Hoxby's evaluation is both systematic enough to serve policymakers determining resource allocations and targeted enough to provide information to parents making school choices for their own children.


Jennifer A. Marshall is Director of Domestic Policy Studies, and Kirk A. Johnson, Ph.D., is Senior Policy Analyst in the Center for Data Analysis, at the Heritage Foundation.

[1] Caroline Hoxby, "Achievement in Charter Schools and Regular Public Schools in the United States: Understanding the Differences" Harvard University Program on Education Policy and Governance working paper, December 2004, at

[2]Jay P. Greene, "No Comparison" New York Sun, August 19, 2004, Editorial & Opinion, pg. 9. This op-ed is based on a larger research report that also uses a matched schools methodology to analyze the differences between charter schools and traditional public schools. See Jay P. Greene, Greg Forster, and Marcus Winters, "Apples to Apples: An Evaluation of Charter Schools Serving General Student Populations" Manhattan Institute Education Research Report No. 1, July 2003, at


Jennifer A. Marshall
Jennifer Marshall

Vice President Institute for Family, Community & Opportunity

Visiting Fellow
Kirk Johnson

Former Visiting Fellow