Michelle Rhee, the hard-charging and polarizing former Washington, D.C. school chief, knew much more than she's let on about the possibility of teacher cheating on student high-stakes tests under her watch. On Thursday PBS's John Merrow published a heretofore secret memo written by a consultant Rhee hired which [suggested](http://takingnote.learningmatters.tv/?p=6232) that teacher cheating was widespread in D.C. schools, including possibly some 191 teachers at 70 schools. Rhee told Merrow that she "received countless reports, memoranda and presentations," and couldn't remember ever seeing this particular document. Yet other district staffers say that Rhee and D.C.'s current school chief Kaya Henderson discussed the memo in meetings. It's a bombshell revelation for Rhee, who built her reputation as a no-nonsense superintendent determined to clean up D.C.'s public schools and who has since has leveraged the national acclaim and notoriety she garnered as D.C. schools chief to become one of the nation's most visible education reformers. The problem is about more than just some adults behaving badly. Teacher cheating has become a serious, widespread problem in the U.S. education landscape. As the mainstream education reform movement, fueled by federal accountability laws like No Child Left Behind and initiatives like Race to the Top, have ratcheted up the use of test scores for determining everything from the stability of a school community to the efficacy of a teacher, people's livelihoods and student's school campuses have come to depend on how well their students performed on standardized tests. Rhee herself was a prominent supporter of this kind of approach.