Peter Greene makes a stab at explaining what Andrew Cuomo doesn’t understand about accountability.

First point is that you keep your promises after the election is over. Cuomo promised to delay high stakes attached to test scores in teacher ratings. After the election, he changed his mind.

The second is that you use tests to learn what’s happening, not to confirm what you believe. Cuomo thinks lots of teachers are failing, and he won’t believe any measurement unless it confirms his prior conclusions.

What Peter doesn’t explain is why presumably intelligent people like Cuomo think that teachers alone are responsible for student test scores. What if the student never does his homework or pay attention in class? What if the student doesn’t speak English? What if her mother has a fatal illness? There are so many variables over which the teacher has no control. Experience has shown that the various teacher evaluation models are fraught with instability and error.