Hurdles Emerge in Rising Effort to Rate Teachers

“If I thought they gave accurate information, I would take them more seriously,” the principal of P.S. 321, Elizabeth Phillips, said about the rankings. “But some of my best teachers have the absolute worst scores,” she said, adding that she had based her assessment of those teachers on “classroom observations, talking to the children and the number of parents begging me to put their kids in their classes.”
It is becoming common practice nationally to rank teachers for their effectiveness, or value added, a measure that is defined as how much a teacher contributes to student progress on standardized tests. The practice was strongly supported by President Obama’s education grant competition, Race to the Top, and large school districts, including those in Houston, Dallas, Denver, Minneapolis and Washington, have begun to use a form of it.
But the experience in New York City shows just how difficult it can be to come up with a system that gains acceptance as being fair and accurate. The rankings are based on an algorithm that few other than statisticians can understand, and on tests that the state has said were too narrow and predictable. Most teachers’ scores fall somewhere in a wide range, with perfection statistically impossible. And the system has also suffered from the everyday problems inherent in managing busy urban schools, like the challenge of using old files and computer databases to ensure that the right teachers are matched to the right students.

　こちらも教育の話題。オバマ大統領によって推進された教員評価制度が現場でどうもうまくいってないみたいです。
　日本も全国共通学力テストがあるけど、それが教員の評価につながったりはしてるのだろうか？