[ryansloan]

Warning: Anecdata follows...

When I was a student, I had some great teachers who were tenured and some great teachers who were non-tenured. However, nearly all my awful teachers did have tenure. A lot of the people I know were in a similar situation. Some were good teachers who got complacent and lazy, and some seemed to have slipped through the cracks from the beginning. Small N, but I can see how tenure definitely creates some messed up incentives.

That said, I think there are two sides to this issue. Making it easier to get rid of bad teachers is a start, but it's also important that there's a good, transparent way of evaluating whether a teacher is good or bad. I know a lot of teachers, and they all feel as if the way their performance is measured is pretty broken. They're measured based on performance on standardized tests that don't test the right things, etc. I think if you want to attract and retain good teachers, you have to establish better metrics, too. With the wrong metrics, what you end up with is a big pool of teachers who are successful at checking off the right boxes.

(I realize this performance measurement thing is a hard problem in just about every industry!)