A Think Twice Review of:

How New York City's Charter Schools Affect Achievement

Think Twice - Nov 12, 2009

Publisher/Think Tank - The New York City Charter Schools Evaluation Project

Author(s) -

This report estimates the effects on student achievement of attending a New York City charter school rather than a traditional public school. A key finding compares the cumulative effect of attending a New York City charter school for 9 years to the magnitude of average test score differences between students in Harlem and the wealthy New York community of Scarsdale.

Reviewer(s) - Sean Reardon, Stanford University

Reardon's review finds that the report "has the potential to add usefully to the growing body of evidence regarding the effectiveness of charter schools." However, it also notes that the report's key findings are grounded in an unsound analysis—an inappropriate set of statistical models—and that the report's authors never provide crucial information that would allow readers to more thoroughly evaluate "its methods, results, or generalizability." He warns that "Policymakers, educators, and parents should therefore not rely on these estimates until the bias issues have been fully investigated and the analysis has undergone rigorous peer review."