Reblogged from THE MERROW REPORT
You know the old fable about blind men touching different parts of an elephant to determine its true nature. The guy who feels just the ear draws one conclusion, the fellow who holds the trunk draws another, and so on. That’s my reaction to the latest article touting the success of the District of Columbia’s teacher controversial evaluation system, IMPACT, appearing in Education Next, the journal published by Harvard and Stanford whose contents tend to skew right. It’s a clear case of limited examination of the available information. Not to say that the authors are blind, just that they haven’t examined more of the elephant.
The authors, Thomas Dee of Stanford University and James Wyckoff of the University of Virginia, generally praise IMPACT, asserting that it has driven out poor teachers, rewarded successful ones, and helped the DC schools improve.
However, Dee and Wyckoff gloss over and withhold critical information, material that their readers really ought to be made aware of. Just consider their bold assertion that DCPS is “the fastest-improving large urban school system in the United States as measured by the National Assessment of Educational Progress.” Maybe so, but why don’t the authors disaggregate the data and dig a little deeper? Probably because the results contradict their thesis.