Yet another powerful rebuttal to the AFT-funded sham study of KIPP by WMU. Mathematica, using student-level data, which is far superior to the aggregate data approach by WMU, just released a report that "found that KIPP schools actually have lower rates of attrition for black males when compared with traditional schools." (emphasis added):

A 2010 study by Mathematica found large, positive achievement effects at KIPP schools even when students who had left the schools were counted as part of the original KIPP group.

But a study using aggregate data sets, not student-level data, conducted by researchers at Western Michigan University, in Kalamazoo, and released last month, raised questions about whether KIPP is serving the same kinds of students as are traditional public schools. That study contended that 40 percent of the black males KIPP enrolls leave between grades 6 and 8. "KIPP is doing a great job of educating students who persist, but not all who come," said Gary J. Miron, a professor of evaluation, measurement, and research at Western Michigan University and the lead researcher for the study, in an interview here in our offices at Education Week last month.

In the working paper, the Mathematica researchers released for the first time attrition rates for different racial and ethnic subgroups of students. They found that KIPP schools actually have lower rates of attrition for black males when compared with traditional schools.

"Our data is showing that KIPP loses black males overall at a lower rate than the local district schools," said Christina Clark Tuttle, a senior researcher for Mathematica, in a phone interview today

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