It’s like judging piety by testing the Bible.

More worrying is the role of scoring in these judgments. For decades educationists have tried to assess the output of schools, and largely failed. They have fallen back on anything they can find that is measurable. The outputs are not happy children or well-adjusted or even well-paid ones, let alone a more productive economy or a more stable society. They are merely exam results and test scores, places in a league table. It’s like judging piety by testing the Bible.

Simon Jenkins, awhile back in the Guardian. In the UK, this is the madness that Thatcher set off all across the pubic sector, including health and education (and soon higher education). Teachers matter, it is just that measuring teachers may wreck genuine attempts to improve teaching (pace Dylan Wiliam).