Sarah Cohodes and Susan M. Dynarski:

This November, Massachusetts voters will go to the polls to decide whether to expand the state’s quota on charter schools. The ballot initiative would allow 12 new, approved charters over the current limit to open each year.

Would the ballot proposal be good for students in Massachusetts? To address this question, we need to know whether charter schools are doing a better job than the traditional public schools in districts where the cap currently limits additional charter school seats.

There is a deep well of rigorous, relevant research on the performance of charter schools in Massachusetts. This research exploits random assignment and student-level, longitudinal data to examine the effect of charter schools in Massachusetts.

This research shows that charter schools in the urban areas of Massachusetts have large, positive effects on educational outcomes. The effects are particularly large for disadvantaged students, English learners, special education students, and children who enter charters with low test scores.