Test the students, Punish the Teachers

In her article in the New York Review of Books titled No Student Left Untested, Diane Ravitch describes how asinine New York's new test-based accountability scheme is:

The new evaluation system pretends to be balanced, but it is not. Teachers will be ranked on a scale of 1-100. Teachers will be rated as “ineffective, developing, effective, or highly effective.” Forty percent of their grade will be based on the rise or fall of student test scores; the other sixty percent will be based on other measures, such as classroom observations by principals, independent evaluators, and peers, plus feedback from students and parents.

But one sentence in the agreement shows what matters most: “Teachers rated ineffective on student performance based on objective assessments must be rated ineffective overall.” What this means is that a teacher who does not raise test scores will be found ineffective overall, no matter how well he or she does with the remaining sixty percent. In other words, the 40 percent allocated to student performance actually counts for 100 percent. Two years of ineffective ratings and the teacher is fired.

If you start with unreliable and invalid data and you add multiple measures you still have unreliable and invalid data.

There's good reason no high-performing nation in the world evaluates teachers by the test scores of their students.