Rhee's Hard Data or "Single Data Points" Depends on Whose Value Is Being Added

Just a few short weeks ago Michelle Rhee and her lawyers announced the firing of a whole bunch of tenured teachers based on first year evaluations under the new IMPACT "value-added" scheme that pays and punishes teachers based on student test scores.  From WaPo:

Rhee, and like-minded leaders in other school districts, contends that the best way to overhaul schools is to intensively monitor the performance of every adult, including janitors, and measure it by multiple yardsticks. For teachers, that includes evidence that their students meet or exceed predicted rates of growth on standardized tests, a metric known as "value-added." School districts have experimented with value-added for many years but generally employ it as a diagnostic tool to assess weaknesses or determine bonuses. . . .

. . . .Value-added constitutes 50 percent of their evaluation. Twenty-six of the 165 dismissed teachers fell into this category. . . . At the end of the school year, the teachers' overall performance was converted to a 100-to-400-point scale. Teachers with scores below 175 are subject to dismissal. Teachers scoring between 175 and 249 are judged under the system to be "minimally effective." Scores between 250 and 400 are considered "effective" or "highly effective." 

According to Rhee and the Oligarchs who built her, one-shot tests appear to be perfectly valid when it come to firing teachers and making decisions on teacher pay and job security.  However, when it comes to Rhee's own accountability to do what she identified in 2007 as her top priority as schools chief (to close the achievement gap), such tests are only isolated data points that should be looked at over time.  You see, the gaps are not closing as Rhee's raging arrogance had led her to predict.  From Rhee's spokeswoman, Jennifer Calloway:

. . . She also cautioned against forming broad judgments on the basis of a single year's data.

"Change does not happen overnight," Calloway said. "Any one single data point - or change in a single data point over one year - is not sufficient to make overall conclusions about progress on this goal. To only consider one year would not accurately portray what has happened during this administration." . . .

Which Rhee to believe depends upon whether you are a former DC teacher looking for work or one of Rhee's stooges who will be looking for work after this year's elections dump the vaguely beige mayor, Adrian Fenty.   But surely Rhee will now re-think her hair-trigger firings of all those teachers based on "a single data point."  About as surely as Arne Duncan making school integration a top federal policy priority.