Charter Schools Are a Winning Strategy

A new national study looking at hundreds of charter schools and charter school systems across the United States has found that, on average, students in charter schools gain 16 additional days of learning in math and six additional days in reading.

The averages, of course, reflect dramatic variation across the sector — many charter schools are achieving outstanding outcomes; others are severely underperforming. In particular, virtual charter school students make up six percent of all charter students and they lose, on average, 58 days in reading and 124 days in math. Meanwhile, Success Academy is providing an additional 206 days — more than one school year — of math learning and an additional 107 days in reading. 

The average benefit for all charter students also obscures the more pronounced advantages for historically underserved students: Black charter students gain an additional 35 days of learning in reading and 29 in math on average; Hispanic students gain 30 and 19 days of additional reading and math learning; and low-income students gain 23 and 17 days respectively. 

The study, which comes from Stanford University’s Center for Research on Educational Outcomes, or CREDO, provides important information about how the sector has progressed since its early days. CREDO's first national study, released in 2009, found that, on average, charter school students learn less than district school peers; its next study, in 2013, found that they performed roughly the same. These findings continue to be cited by charter school opponents as a reason to be skeptical of charters, even though both studies found significant benefits for subgroups of students (e.g., Black, Hispanic and/or low-income) and smaller subsequent CREDO studies identified districts, states, and structures where charters had outsized positive impacts.

CREDO’s most recent study offers essential and conclusive evidence that, as a public policy, charter schools are a resounding success: Not only are students in these schools learning more overall, but the schools are clearly superior at continuous improvement. Even with exponential growth since 2009, the sector as a whole has gotten better at educating students. Meanwhile, achievement at district schools flatlined during the same period, despite increased funding and many efforts at reform.

The key lesson is that while charters’ governance structure — flexibility in exchange for accountability — is not a guarantee of success, it is a powerful precondition for ongoing school improvement and outstanding achievement. I’d love to believe that these findings will change the minds of charter school opponents, but facts rarely make a dent in ideology. For those who ground their beliefs and actions in evidence, however, the policy implications are clear: Expanding high-performing charter schools is a winning strategy for righting the structural inequities of our district school system and addressing our country’s achievement crisis.