When is cheating not cheating? When it happens in a charter school whose owner is politically powerful. When it threatens the very foundations of test-based accountability, the foundation of No Child Left Behind and Race to the Top.

Ask me no questions, I’ll tell you no lies.

The story begins:

“The odds that 11th-graders at Strawberry Mansion High School would have randomly erased so many wrong answers on the math portion of their 2009 state standardized test and then filled in so many right ones were long. Very, very long. To be precise, they were less than one in a duodecillion, according to an erasure analysis performed for the state Department of Education.

“In short, there appeared to be cheating — and it didn’t come as a total surprise. In 2006, student members of Youth United for Change protested being forced out of class for test-preparation sessions and won concessions from the district. In 2010, principal Lois Powell-Mondesire left Strawberry Mansion; after her departure, test scores dropped sharply.

“But despite the erasure analysis and those suspicious circumstances, neither Powell-Mondesire nor any other teacher or administrator at Strawberry Mansion was ever disciplined. On the contrary, Powell-Mondesire was promoted — to a job at school-district headquarters, earning more than $145,000 as a “turnaround principal” charged with helping other administrators boost student achievement. (Powell-Mondesire, who retired July 1, could not be reached for comment. Neither the District nor the state would say whether her exit was related to the cheating investigation.)…

“After all, politically, the state would have a great deal to lose by prosecuting cheaters. Some of the most damning evidence of cheating has come from Philadelphia, a district run by the state since 2002, and from charters, including a Chester school run by a prominent leader in Pennsylvania’s self-described school-reform movement who is a backer of Gov. Tom Corbett. But more than that, bubble tests have become the high-stakes centerpiece of American public education; when the scores are tainted, it could throw an entire way of running schools into question.

“Given the scope of the issue and the lack of action since, it appears Pennsylvania is covering up one of the country’s largest cheating scandals — and doing so in plain sight.”