Mathews carefully concedes:
Thank goodness then for the cautious, balanced analysis provided by Henig, an expert on urban education reform and charter schools at Columbia's Teachers College. He agrees with KIPP officials that they have not been selecting just an upper crust of higher-scoring and better motivated kids for their schools, despite suggestions to the contrary. But he also points to a possible flaw that leads some students to return to their regular public schools before completing the KIPP middle school program, perhaps because they find the work too hard and the days too long. Their departure may distort reports of KIPP gains. Turnover of KIPP teachers, he says, is also high and creates doubt about whether gains can be sustained.
The funny thing is, Henig wasn't telling Mathews anything he didn't already know. KIPP's push-out of low-scoring kids is old news. Mathews even read the same critique of KIPP last May when he reviewed the book, Keeping the Promise: The Debate Over Charter Schools.
Henig must have an antedote for Kool-Aid.