I would argue this is exactly what a worse teacher does. They can discourage/mislead/destroy 100s or 1000s of students over their career which can have dramatic effects for a society.
I agree with you. But I think the problem is that our society doesn't really know what that is until many years after the fact and its really hard to measure. Personally I would absolutely support a policy where teachers who have better test scores (by some metric. Same district? same city? same state? raw numbers?) get more money. A company can pretty easily see X brought in more than Y revenue. Tough for a school.
ecshafer|2 years ago