Education Next

“Boston and the Charter School Cap”

Imagine you live in a city with a set of open-enrollment public schools, serving predominantly low-income children of color, where students learn at twice the rate of their peers in neighboring schools. And what if those high-performing schools were ready, willing, and able to enroll more students, maybe even double or triple in size? Sounds too good to be true, huh?

Well, that city actually exists, and it’s Boston. But, remarkably, the powers that be are blocking the city’s best schools from growing for the simple reason that they are charter schools.

…[A} research team, led by Josh Angrist and Parag Pathak, directors of the School Effectiveness and Inequality Initiative at MIT, compared “long-term outcomes” of Boston charter-school students to outcomes for BPS students who had entered charter-school admission lotteries. Unlike previous studies, which focused on MCAS results, the MIT report tracked performance on Advanced Placement and SAT tests. It also looked at the number of students qualifying for scholarships to state colleges, along with postsecondary enrollment data. The study found that Boston charter schools doubled the rate of AP test-taking, boosted composite SAT scores by more than 100 points, and increased enrollment in four-year colleges by almost two-thirds. The MIT authors conclude that previous findings of strong MCAS performance in middle school are consistent with later measures of academic success, specifically those that are indicators of improved college readiness. “The effects of Boston’s charters are remarkably persistent,” they write.