Yeah, I have had a few not so good teachers.

The problem is that the profession isn't respected or paid well, so the best and most competent teachers usually move on to where they will be respected and get paid what they are worth.

Another problem is that unions, not just teacher's unions, but all unions, don't make it easy for employers to get rid of the incompetent workers. I myself over the years have belonged to 3 different unions, although one, the Screen Actor's Guild, was more of a guild than a labor union, but at a time when unions were greatly weakened by Reagan and other republicans, so the benefits of belonging were only slightly better not belonging. Anyway, I think it would make unions a lot stronger if they came up with some way to weed out incompetence. It would make their workers more valuable, as they would retain the most skilled workers.

Anyway, back to teachers. If teachers were respected and paid what they are worth, perhaps more of them would care more, and the best teachers wouldn't leave for greener pastures. I'd like to see teachers who don't really like kids to being with get fired, rather than get tenure.

I had a friend whose parents are wealthy, and he chose to be a high school teacher teaching advanced math to mostly autistic kids. His family keeps asking him when will he get a real job. He likes what he does, but he teaches at private schools because public schools don't pay enough for him to live off of.