" ...in Illinois, one in 57 doctors loses his or her medical license, and one in 97 attorneys loses his or her law license, but only one teacher in 2500 has ever lost his or her credentials."
While looking for the source of this claim, which is repeated without citation in the movie and its companion book, I came upon a2007 newspaper article by Scott Reeder, of the Small Newspaper Group:
During the past six years, 1 in 2,500 Illinois educators have lost their teaching credentials through suspension, revocation or surrender. By comparison, during the same period 1 in 57 doctors practicing in Illinois lost their medical licenses and 1 in 97 Illinois attorneys lost their law licenses.
Since the movie was released, these figures have been repeated frequently, taking up five pages in the Google search engine, and were cited in The New York Times review, the British Independent, as well as on the Brian Williams-hosted television program Education Nation on NBC.