This report evaluates the current state of research on New York City charter schools. Overall, their effect on student performance is unambiguously positive. But the research is more dated and limited in scope than proponents and critics of charters appreciate.
- Students who attend a New York City charter instead of a traditional public school do much better on math tests and better, but by a smaller amount, on English language arts (ELA) tests. These positive effects appear to have remained similar over time, even as the number of charters and students has expanded. However, the studies that employ the strongest potential research design are dated or targeted only at a few highly effective schools that do not represent the full charter sector today.
- New York City charter schools are not equally effective. About half appear to be more effective than the traditional public school that students would have otherwise attended. A small percentage of charters appear to have negative effects on student test scores.
- Differences in resources do not explain differences in effectiveness between charter schools and traditional public schools or between charters in New York City.
- There is no evidence that New York City charter schools systematically push out low-performing students. In fact, low-performing students are less likely to exit charter schools than they are to exit traditional public schools, especially after accounting for differences in their demographic characteristics.
- Competition from New York City charter schools has either no effect, or a positive effect, on the performance of students in the nearby traditional public schools.