At ds's last school (primary in a very naice area), his worst meltdowns, starting as soon as he got in the car, we're following days where he was picked on by two NT boys. They were well known for picking on the children with SN.
One child was followed home every day and had stones thrown, he was tripped up, they called him retard. They did this in school as well and teachers turned a blind eye to it all.
I went to see the HT about it, she blanked the issue and wouldn't even acknowledge it.
Teachers in that school were very bad at dealing with the dc with SN, they mentally poked and prodded them, showed no understanding, gave no support.
The bully boys came from very well to do families, and school simply did not want to have to tackle them about it.
The dc who had meltdowns and lashed out in school all did so because of bullying and poor management.
It doesn't always have to cost the school money to help dc with ASD, but a slight change in language used, attitude towards them, trying to understand their difficulties, tackling bullying straight away, lots of basic things like this which are ignored.
In school, ds (PDA) is called lazy for asking for help, he's told off for stimming (because it doesn't look like stereotypical stimming probably), he is often rude to the TA because she is strict and demanding in a "do this because I said so" kind of way, he is told off for getting giddy in pe, even though they know he also has spd, he's told off for ignoring teachers when it all gets too much.
But they can't see any ASD behaviour at all 
Ds comes home every day at the moment and melts down, we spend every fucking evening supervising him, chucking junk food in the oven because there's no chance to cook anything decent, we have to keep him split up from his siblings or he'll hurt them, he's refusing melatonin half the time so not sleeping until very late.
But we're the lucky ones because he's "fine" in school.
I have no idea if better strategies in school, which would cost nothing to put in place, would help, because no-one will fucking try!
Yet we're the shit parents because our son hurts us and we "let him get away with it".
School are obviously doing it right because he's "fine" there.
HE'S NOT FINE, HE'S MASKING. THERES A DIFFERENCE.
Sorry, bad morning and getting really down that apparently school do not care about one of the dc in their care, his future and well being, and that of his family, who are not coping well at the moment.