There has to be some sort of guideline established to rate teacher performance. Student grades seem to be the best way to do this. If a certain teacher produces classes with substandard grades over and over, it would seem to me that there is a problem and most likely it would be a poor learning environment. Certainly steps should be taken to improve this situation. It would seem that teachers who will not accept this fact and have a genuine desire to improve their profession overall is more interested in pay than performance.
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