Growing up in the 80's and 90's I seemed to have teachers who were either absolutely fantastic or utterly awful.
In primary school I had a female Scottish teacher who would stand in the boys toilets and watch them using the urinals under the claim she was making sure nobody was being naughty, she didn't stand around in the girls bathroom and none of the other teachers did anything like it. At the time I didn't think to mention it to my mother, despite being uncomfortable with it the teacher was quite authoritarian and I was worried I'd get into trouble if I said anything. Looking back I find it a little bit creepy, I told my mother about it years later and she was pretty shocked. There was another teacher I had briefly when I was around 7-8 who was a temp hire to cover my normal teacher who was ill, she spent half of each day ranting about how she wasn't scared of kids because she used to work in prisons. Would make 'naughty' children stand on their chairs for however long pleased her, even went so far as to try and keep the entire class back for after school detention for some perceived slight while our parents were stood outside waiting to pick us up. She was given the boot after a few days when all the furious parents went knocking on the headmasters door.
I had an English teacher in secondary school who would sing 'Who ate all the pies' every time a certain chubby kid walked into his classroom. There was another English teacher who once threw a hardback book off my head because he thought I wasn't doing any work, a mate of mine was a short little beggar and he actually picked him up off the ground and hung him by his coat off the rooms coat hangers/wrack. I also had a French teacher who was pretty authoritarian and strict, she once made the same guy who got hung by his jacket do laps around the language block with no coat on while the ground was thick with snow because he didn't do his homework. Funnily enough she was actually the sister of the English teacher who accosted him.
Kids being told they were useless or wouldn't amount to anything was the least of the crap some of the kids I went to school with had to deal with from teachers.
I've a ton of stories like the above from my years at school, honestly in hindsight we probably could have got a lot of teachers sacked if we'd pushed the issue or taken it to our parents, but the ones who used to get the crappy treatment were generally labelled (rightfully or wrongfully) as trouble makers and were afraid to say anything most of the time.
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