I just want to get some advice please, hopefully 
Bit of background and I'll try not to ramble...
My DS is almost 13 in year 8. He's got a lovely nature albeit very (I think) immature, in that he can be silly - saying silly things to other kids, probably including his friends. He is at middle school so due to move up to high school in September, to year 9. In the past few months I suppose if I'm honest, he has had a few fall outs with his peers, not necessarily 'friends' but boys in his school, in the same year. From what he tells us - and he has been known to stretch the truth! it might start with someone calling him a name, so he'll call one back, then the boy might shove him or push him, so then DS will walk away. It has also happened during May half term, he rode on his bike to get some sweets, saw 3 boys he knew from school, hoe called him over and asked what he was doing, when DS replied getting some sweets, the boy said 'give me 50p' to which DS replied No, so the boy punched him on the arm. when I asked DS what he did back to the boy, he said I couldn't do anything as the other 2 would have stuck up for --- (the boy.)
This is just 1 example of the maybe twice a week, incidents which happen at school. Both me and my husband have told him that no one should be allowed to push him around at school, or anywhere else, and if it happens again, he should push the boy concerned back.
It is not just boisterous fun either; there have been school day trips and DS was sat on the coach on his own on the way back. He did sit with a friend on the way out but was on his own on the way home - I don't think he had upset the friend (!) but they had just agreed one way. Parties - lots of kids (at least 4 recently) have had biggish parties, celebrating turning into a teenager, DS not been invited but his friends have.
He has had 'help' at school from a weekly session with one of his form tutors, she is employed as a sort of counsellor by the school too, to try and help him with getting along with peers etc. But from a 'bullying' perspective (pushing and shoving etc) the school don't want to think any of that goes on at their school.
I just want him to start at his new school in September hopefully more mature, and to be able to get along with boys in his year. DH although worried too, said tonight maybe it's just boys being boys and it's just a phase.
The fact that he's not very academic doesn't help either I think, in that maybe he genuinely doesn't understand how annoying it can be when someone says something silly/unkind.
Deep down, I know my DS is a great kid, he has a sunny happy go lucky personality but I just want him to be accepted a bit more, and to mature a bit.
Does anyone else have experiences similar to this with their boys? (Or girls!)
Thanks for reading x