I don't see a problem with effective metrics; they might help identify where teachers might need help. The problem, is that usually nobody really does proper s

I don't see a problem with effective metrics; they might help identify where teachers might need help. The problem, is that usually nobody really does proper statistical analysis. The metrics I've seen, are usually like "mean student grade performance". In which case, what you'd want to do is have a really small class of smart kids. (Ergo, kudos to the teacher who finds a way to dump the idiots.) I do think, however, you could do polling of teachers by asking the students, teachers, and other staff. In most cases you could easily have enough coworkers to figure out who's respected and who needs help.