From EdNews.org:

The study found a testing performance gap between New York City charter school students and those who applied but did not get in.

Students who entered lotteries and won spots in New York City charter schools performed better on state exams than students who entered the same lotteries but did not secure charter school seats, according to a study by a Stanford University economist being released Tuesday.

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By the third grade, according to the study, the average charter school student was 5.3 points ahead on state exams in English compared with students who were not admitted to the charter schools. In math, the students were 5.8 points ahead. Most tests are scored on a scale of roughly 475 to 800.

Charter school lotteries allow researchers to conduct natural experiments because students are randomly assigned to groups (admitted vs. denied admission).

For those still hung up on the results of the CREDO study, read Dr. Caroline Hoxby’s memo titled “A Serious Statistical Mistake in the CREDO Study of Charter Schools.”