High-Quality Charter School Report Confirms Past Research
June 24, 2009

CREDO study reinforces evidence showing no overall impact of charters on student achievement, according to new review

Contact: Teri Battaglieri, (517) 203-2940;
Gary Miron, (269) 599-7965;
Brooks Applegate, (269) 387-3886;

EAST LANSING, Mi., June 24, 2009 – A new report on the impact of charter schools on student performance finds that, on average, charter schools perform no better than traditional public schools. A review of the report finds that the solid analytic approach employed and the comprehensive data set used make the report a valuable addition to the body of charter school research.

The report, Multiple Choice: Charter School Performance in 16 States, is from the Center for Research on Education Outcomes (CREDO) at Stanford University. It was reviewed for the Think Twice think tank review project by Gary Miron and Brooks Applegate of Western Michigan University who have extensive experience studying and evaluating charter school performance.

Multiple Choice draws its conclusions from the researchers’ examination of longitudinal, student-level data compiled from 15 or 16 states (the reviewers note some lack of clarity on this point), covering 65-70% of the nation’s charter schools. The report analyzes the achievement of students in these charter schools compared to that of matched students in traditional public schools.

The primary findings of the CREDO report show that charter school students’ test performance is basically the same as the performance of students enrolled in traditional public school. Because of their very large data base, the authors were able to tease out statistically significant differences in 54% of the charter schools studied, with the following results: “17 percent [of charters] provide superior education opportunities for their students. … 37 percent, deliver learning results that are significantly worse than their student would have realized had they remained in traditional public schools.”

In their review, Miron and Applegate summarize past research examining charter school performance and indicate that the CREDO findings strengthen the broader body of evidence which shows average charter performance to be equal to, or perhaps lower than, the performance of  traditional public schools.

The CREDO report also attempts to draw some state-level conclusions from their results, looking at three policies associated with more or less restrictiveness in the state charter laws: caps on the number of allowed charters in the state, restrictions on who can authorize the creation of a charter, and the allowance of appeals by charter applicants from a denial of authorization. The results were mixed, and the reviewers conclude that the analytic approach was undermined by the divergent manner in which these policies are implemented. The reviewers do, however, present their own secondary look at the state-level data (presented in their review) and uncover a pattern showing states doing better when they have fewer charters and when fewer of those charters are run by for-profit corporations.

Although too complex to be easily summarized, the review from Miron and Applegate also raises a series of technical questions regarding the report’s analyses. Because of the potential value of the CREDO work, the reviewers urge the authors to answer those questions in technical follow-up papers to the report and in later work with their data base.

Find Gary Miron’s and Brooks Applegate’s review as well as a link to the Stanford CREDO report on the web at:

About The Think Twice Project
The Think Twice project provides the public, policy makers and the press with timely, academically sound reviews of selected think tank publications. It is a collaboration of the Education Policy Studies Laboratory at Arizona State University and the Education and the Public Interest Center at the University of Colorado at Boulder and is funded by the Great Lakes Center for Education Research and Practice.


The mission of the Great Lakes Center is to improve public education for all students in the Great Lakes region through the support and dissemination of high quality, academically sound research on education policy and practices.

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