New York City charter schools are closing the Scarsdale-Harlem achievement gap, concludes Stanford researcher Caroline Hoxby in a new study. Low-income, minority students who attended a charter school from kindergarten through eighth grade closed 86 percent of the achievement gap in math and 66 percent in English language arts compared to affluent suburban students in Scarsdale. For each year spent i a charter school, students are more likely to earn a Regents diploma. Some 30,000 New York City students attend charter schools, while 40,000 sit on waiting lists trying to get in. Charter students outperform similar students who lost charter lotteries, the study found.
A 15-state study by the Center for Research on Education Outcomes, also at Stanford, found most charter students do not outperform students in nearby public schools, reports Ed Week’s Debra Viadero. Some speculate that New York City charters are better than charters in other locations.
But another possible explanation for the sharply contrasting results, said Ms. Hoxby, may be that the CREDO findings suffer from a “serious mathematical mistake.” The problem, she said in a separate analysis, is that (Margaret) Raymond compared the achievement of individual charter students with that of groups of students from nearby public schools, without making the statistical adjustments necessary to account for the natural downward biases that result from that sort of calculation.
Hoxby’s research found successful New York City charters have a longer school year.
Likewise, researchers found that the average charter school in the study stayed open eight hours a day, with some providing services for as long as 10 hours.
Other school characteristics associated with better student achievement included: more time spent on English instruction; teacher pay plans that were based on teachers’ effectiveness at improving student achievement, principals’ evaluations, or whether teachers took on additional duties, rather than traditional pay scales; an emphasis on academics in schools’ mission statements; and a classroom policy of punishing or rewarding the smallest of student infractions.
Class size, parent contracts and number of years in operation did not correlate with achievement. , according to the report.