The stock of rigorous studies demonstrating the positive effects of charter schools on student achievement just became a little larger with the release of The Manhattan Institute’s latest report, Charter Schools in Newark: The Effect on Student Test Scores, looking at Newark, N.J. This is important news as charter school expansion was a major part of the city’s reform efforts that began in 2010. In addition to accountability for all schools, these major reforms included a common enrollment system that allowed parents to apply to many schools (both charter and traditional) in one place rather than each school separately. Marcus Winters—the study’s author, an associate professor at Boston University, and a senior fellow at the Manhattan Institute—leveraged the city’s common enrollment system and the deferred acceptance lottery-based assignment mechanism to provide plausibly causal estimates of the effect of enrolling in a public charter school on math and ELA test scores.
The study finds that enrolling in a charter school has large positive effects on both math and English language arts (ELA) test scores. The effects are sustained in each of the three years of study and are roughly equivalent to a 2% increase in lifetime earnings. The study also finds that these effects are consistent across traditionally disadvantaged populations. Finally, the study demonstrates that these gains are larger in KIPP and Uncommon schools.
Critics often argue that positive findings on student performance in charter schools are not because charter schools are any better, but because they enroll different types of students—making it easier to produce gains—and that they push out poor-performing students to inflate test scores. This report directly addresses both criticisms. The author’s approach ensured that the students in his study had similar observable characteristics such as prior achievement and disadvantage, and likely similar non-observable characteristics such as parent engagement. Plausibly, the only difference is that one student went to a charter school and the other did not. This study also measures later outcomes for students regardless if they remain in the charter school. Because the effects are sustained throughout the study period it is highly unlikely that schools are pushing out students to generate positive outcomes.
And, this study combats another common criticism—that the presence of charter schools puts fiscal pressure on district schools and results in poorer outcomes for students in traditional district schools. A quick scan of the New Jersey Department of Education’s website shows that operational spending per pupil was somewhat higher to roughly the same in Newark’s traditional district schools than its charter schools, suggesting that the presence of charter schools is not having an undue influence on the resources available to the district. District-wide performance that the traditional district schools are improving, which is consistent with earlier studies that evaluated the overall reform effects on all schools in Newark.
This study shows that good things are happening in Newark’s charter schools in terms of student achievement. Coupled with other evidence, there is reason to believe that the presence of charter schools and the policies that support accountability and access for all public schools in Newark have created an educational environment that can support students in both traditional public and public charter schools.
Nathan Barrett, Ph.D., is the senior director of research and evaluation at the National Alliance for Public Charter Schools.
