Chris Walters, who earned his PhD in economics from MIT this month, may have the answer to a key question about the impact of charter schools on student performance. Jay Fitzerald of The Boston Globe reports that after more than two years of research, Walters was able to arrive at the conclusion that low-income students who performed poorly on Massachusetts standardized exams while they were enrolled in public schools performed much better after transfering to charters.
This is a momentous finding because it lays to waste the frequent argument that charters only perform better in the state because they have selective admissions policies that "cherry-pick" the best students. On the contrary, according to Walters, low-performing students actually showed more of an improvement after switching to a charter than did their peers who had been performing well in public schools.
Walters also concluded that an expansion of charter schools in Boston would help more poorly performing students in the city — if parents of those students apply to charter schools. At the same time, he warned, expanding charter schools is not a cure-all for closing achievement gaps; at a certain, but unspecified, point, the addition of more charter schools no longer produces the same gains in academic achievement.
Josh Angrist, an MIT economist and one of Walters's advisers, said Walters's findings have crystallized key issues in the debate over charter schools. While the weakest students benefit the most from charter schools, he said, their parents, paradoxically, are the least likely to apply for them to go to charter schools.
Studying the impact of charter schools in the state has been the research goal of Angrist and others at MIT for a number of years. Research out of the university showed that state-funded charters tended to have the most positive impact when they were located in an environment in which student population was demographically mixed, typical of urban centers. Angrist attributes to difference to the unique approaches taken by charters in the urban and suburban environments.
While Boston-area charters tend to become a more rigorous version of traditional public schools by pushing longer hours and tougher classes, suburban schools often toyed with alternative educational philosophies.
Walters's study builds upon previous MIT findings tied to Boston's 25 state-funded charter schools, excluding the four separate charter schools funded directly by the city. About 8,000 students attend charter schools in Boston and 32,000 students attend the 75 charter schools across the state, according to state education officials.
Dr. Kamal Chavda, the chief data and accountability officer for Boston public schools, said he has read Walters's study and talked to him about the results. Even though he's cautious about expanding the number of charter schools in Boston, Chavda said Walters has provided policy makers with rich and original data to review and mull.