(Washington Post) News last week that Tony Bennett, the former Indiana superintendent of public instruction, quietly altered the state grade for a charter school founded by a campaign donor has raised questions about the validity of the trendy A-to-F grading system used to assess schools in more than a dozen states.

Bennett resigned from his job as Florida education commissioner on Thursday amid revelations that he directed staff members to alter the grade of the charter school last fall, when he was Indiana’s schools chief.

E-mails obtained and published last week by the Associated Press show that Bennett was alarmed in September 2012 when Christel House Academy, a charter school founded by Republican donor Christel DeHaan, was about to be labeled a “C” school by the state’s annual grading system. DeHaan has given more than $2.8 million to Republicans since 1998, including $130,000 to Bennett, who was elected Indiana superintendent of public instruction in 2008.

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