Texas Education Commissioner Michael Williams might intend to impose an A-through-F grading scale for rating the state's public schools, but it isn't because advisory committees recommended it.Contrary to what Williams implied while testifying before the Senate Education Committee Tuesday, two panels that spent many months devising a new method of measuring school performance overwhelmingly disliked using A-F.And public comments submitted to the Texas Education Agency on the proposed accountability changes had nothing good to say about the scale preferred by Williams, Gov. Rick Perry and some legislators.Those comments called A-F rankings stigmatizing, degrading and "an anachronism" when Texas is trying to improve, innovate and reform to prepare students for the future."This is setting up our schools for inaccurate public perceptions and does not tell the entire story of how a campus or district is performing," said one commenter, whose name is not included in a compilation from TEA that's online at bit.ly/17fkqbZ.Under the old accountability system, which was based primarily on student scores on the Texas Assessment of Knowledge and Skills (TAKS), schools were rated exemplary, recognized, acceptable or unacceptable.But with the transition to the State of Texas Assessments of Academic Readiness (STAAR) -- which was mandated by the Legislature -- Williams' predecessor, Robert Scott, appointed panels of administrators, teachers, legislative staffers, academics and business people to revisit the factors that school ratings take into account.The committees proposed a composite score that would consider four main areas: student achievement, student year-to-year progress, closing of performance gaps and college/career readiness of graduates. (bit.ly/13UTeAi)Districts and individual schools then would be rated as "met standard" or "improvement required." Those that meet minimum standards could receive exemplary, recognized or other special designations for doing an outstanding job. (bit.ly/Z4xdY6)HB5, a wide-ranging education measure that passed the Texas House in March and is pending in the Senate, includes a requirement that schools and districts be given a rating of A, B, C, D or F.It's possible that an A-F scheme could be adapted to provide a meaningful reflection of what's actually happening in schools, rather than resulting for some campuses in the equivalent of a shaming scarlet letter.But Williams' defense of the simplified scale as "a system that we all grew up with" begs for perspective: He's almost 58; other key proponents are older and would have gone through school in the 1950s and '60s. Surely they wouldn't also prescribe blackboards and chalk for tackling Texas' current and future educational challenges.