Minnesota’s charter school students are gaining about 14 days of learning in reading annually over like sets of non-charter district students, according to an analysis of growth in state test scores.

The analysis, conducted by the Center for Research on Educational Outcomes at Stanford University, found the charters seven days behind on math, but the analysis deemed that data not statistically significant.

That’s considerably better than a similar analysis in 2009, when reading scores were 14 days behind for Minnesota charter students and 21 days behind for math. Nationally, the shift was smaller but also positive for charters in reading, and they improved in math from behind in 2009 to parity now.

The outcome suggests that poorly performing charter schools are closing in Minnesota, and being replaced with new schools that produce superior results. Al Fan, executive director of Charter School Partners, which advocates for high-quality charters, said the data reflect the emergence of gap-closing, high-quality charters such as Global Academy, Hiawatha Academies and Harvest Prep.

The most recent analysis looks at three years of growth, and is based on the Minnesota Comprehensive Assessment. It compares growth by students who scored at the same spot at the beginning of the study period.

Although the study compared growth among students with similar demographic characteristics from charter schools and the public schools their students would otherwise attend, it didn’t adjust for the length of a school’s academic year. Some of the state’s higher-performing charter schools are in session for 20 or more days longer than comparable public schools. Fan said simply adding days or hours isn’t as important as pairing that with quality instruction.

Although the study broke down national data to look at subgroups by race and income, it did not do so for Minnesota. Center Director Margaret Raymond said that’s because of lack of funding.


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