I think you need to read more newspapers about school teachers/education in general and you can find this kind of incompetent nonsense anywhere. I have a teacher back then who stole my achievement by claiming my work (and a friend in my team) as his in an international competition and he's taking the award, we complained to the school and they shut it down to preserve their reputation. Shitty teachers like this exist, you're just probably being very lucky never got them in class.A bullshit scenario so forcefully contrived, even the scanlators couldn't stay quiet.
There is no school on the planet (Russia maybe?) where a teacher would behave along these lines when faced with a situation like this one. We all know she didn't do it and in a few chapters we'll prove her innocence, even if the real mastermind behind isn't revealed....
What do you think a reasonable parent of a wrongly accused student would do to that school?
Shit like this makes it hard to read on since the scenario is completely unbelievable. If part of her defense turns out to be the handwriting not matching hers, or email address the 'evidence letter' came being someone else's, like the 'bullied' girl - something cursory that anyone with half a brain should have picked up on from the start - then I blame the editor for letting the author submit this shit.