I’m honestly not surprised he panicked when he found the door locked. I think most adults would get a fright in that situation, let alone a child who’s already running on fumes in a classroom environment! A fight/flight reaction is a human response, not “bad behaviour”, and it seems odd to me that a single incident like that (especially one caused by a substitute teacher not understanding his needs) would be used as evidence towards suspension. It doesn’t sound like a particularly supportive approach from the school. They seem to be reacting to behaviours rather than understanding what’s driving them.
And I do think as they get older, they naturally develop a bit more ability to self-soothe and regulate, but only if they’re actually given the tools to do that. Fidget toys, movement breaks, clear escape routes, predictable routines, typing instead of endless handwriting… those things aren’t “optional extras”. They’re what allow an ADHD child to participate without constantly tipping into overload.
To answer your question... yes, my son does find the medication helpful for school. He’s calmer, more able to hold a thought long enough to get it onto a page, and his exam scores have gone up by about 30%. But I do have mixed feelings. He’s less excitable about the things he loves, for example he used to be full of joy riding his pony, and now he sort of plods along a bit more flat, even though he says he still wants to ride. It’s like the highs aren’t as high, in the same way the lows aren’t as low. Hard to describe, but it’s definitely noticeable. He’s on Medikinet XL. I try to give him a break in summer, but that means slowly ramping up the dose again each September.
One thing I’d flag is exactly what you described, the “not remembering” if he misbehaved. That is completely normal for ADHD. A lot of the time they genuinely don’t realise they’re not doing what’s been asked, because their body is just doing its own thing. Some teachers interpret stretching or spinning or not sitting exactly in a circle as “misbehaviour”, and then he’s being told off for something he didn’t even register he was doing. That level of constant correction can absolutely hammer their self-esteem, and that was one of my biggest reasons for eventually trying medication.
There are real positives to ADHD like creativity, hyperfocus, emotional intensity, humour. My fear is always that school knocks those out of them by constantly treating their way of being as a problem. The traditional school model just isn’t built with ADHD in mind. It's basically sitting still for long periods, heavy handwriting demands, no movement, minimal sensory support, and very little flexibility. There’s nowhere else in life where you’re expected to sit motionless and absorb boring instructions for hours on end.
On home ed, just my personal view, but I wouldn’t. School, ideally, teaches them how to navigate people, friendships, conflict, group expectations, not just academics. And if he likes the school socially, that’s a really great start. If it’s the school struggling with him rather than the other way around, then really they should be adapting. A single nervous classmate shouldn’t automatically trump his entire positive experience, especially when the incident wasn’t targeted at her and was a normal stress reaction caused by the school locking him in and not understanding his needs.
On the handwriting, yes absolutely look at OT, and also at dysgraphia. It’s not that they “can’t write”, it’s that writing is physically painful and the cognitive load is huge. They have to think of the idea, hold it in their head, plan the sentence, spell it, and physically produce the letters, all while battling ADHD working memory issues. Typing reduces one part of that burden. We also found playing with putty is helpful for hand strength, and getting him to talk through what he wants to write before putting pen to paper - this made a noticeable difference.
It’s not easy, and you’re doing everything right by actually trying to understand him rather than punish him. He sounds like a lovely boy who genuinely wants to do well, so try not to feel too disheartened by the school, I know it's hard, but it sounds like you might need to educate them a little about what he needs so he can be the best version of himself.