Here we go ...
I was in class in high school, and I found a pen under the desk. Not an ordinary cheap plastic throwaway pen, it was one of those expensive metal pens that telescoped together to pop in and out, with gold trim and enamel cloisonne all along the barrel, the sort that you would give someone for an expensive birthday present. Eager to do the right thing, I put my hand up and told Mr Schulz, asked if I should take it to the lost-and-found at the front office. "No," said Mr Schulz, "give it to me and I'll keep it in my desk here". It occurred to me that he uncharitably thought that I was going to get "lost" on the way there or back, instead of sitting in his lesson; I thought that he would hand it in to the front office on my behalf.
The policy at school was that if no-one collected an item from the lost-and-found, you could go and claim it. So a few weeks later, when I asked at the front office, I was surprised that the pen hadn't been handed in. I asked Mr Schulz about it, and he took the pen out of his drawer, and used his Swiss Army Knife to etch my name into it, saying that I might as well keep it, because no-one had claimed it.
Of course, within a few days one of the other boys saw me using it, and decided that I had stolen it from him. Before I could find Mr Schulz to get him to verify my version of events, he and several of his friends caught me in the corridor between lessons and beat me black and blue. Two black eyes, and so many bruises that I couldn't walk properly or stand up straight for weeks. My parents said "You must have done something to deserve it", took no action against the school, and made me go back to school the next day anyway.
I was summoned to the deputy headmaster's office. He told me that since I had stolen this pen from the other boy and put my name on it to make sure everyone thought it was mine, I was a disgrace to the school and would be put on detention (picking up litter before and after school, and at lunchtime, no canteen privileges, no excursions) for the rest of the year. I protested my innocence, so Mr Schulz was summoned, he promptly denied all knowledge and involvement, and straight up called me a liar.
Word had got around to all the teachers; by hearsay they also all decided that I was a thief and a liar, and gave me extra work to punish me, on top of my regular homework. I was now doing homework from the moment I got home until way past midnight, and in the mornings at 6am when my parents woke me up until 8:30 when I had to ride my bike to school.
I pretty much gave up on schoolwork, because if the teachers were going to lie, there was no way to know if what they were teaching was the truth, and if I asked questions about the problems I was having, especially in maths and physics, I was told to stop disrupting the class, because they had decided without evidence that I was a "juvenile delinquent" and not worth helping.
I had several serious bicycle accidents riding to and from school during this time, and I'm absolutely certain that it was because I fell asleep from pure exhaustion. I still have scars from those accidents, and I'll always remember how I got them.
I left school at the earliest opportunity, left my parents and lived on the streets for a few years, and thanks to a charity helping street kids, got an apprenticeship and a place to live. A few years after that, I sort-of-almost reconciled with my parents, who still believed the teacher's version of events, because "all teachers are good, honest, respectable people".
Throughout my own children's education, I always had anxiety attacks when I had to take them to school, or go to school for parent-teacher meetings etc, even though they attended a different school and we now live several states away.
That was over forty years ago, and I still feel like Mr Schulz both derailed my education, and ruined my plans for further education.
"School days are the best days of your life" -- I think not.