I wonder if it is the school? How good are they with boys? Do they cope as well with boys as with girls?
I would calm down. Shouting does not good. Removing privileges should not generally be necessary if school deals with incidents.
I would suggest buying something like How to talk and trying alternative parenting techniques.
I would especially recommend: 1) rewarding good behaviour, and making sure you spot it every day! 2) Make sure he gets enough exercise, including before school, walk or park further away and walk, or something 3) If he can't cope keep a food diary; orange juice really sent my son crazy.
Go and talk to the school, and see what they suggest for his behaviour in schools. What are they going to do? What do they want you to do? Keeping a diary of home/school contacts might help. Is the SENCO involved? If it is a serious issue they should be.
I don't know the answer, but I'd keep an open mind and read everything I could. Hit Amazon, or even better your library or bookshop and browse with your cynical side switched off. Some starting ideas- Raising Boys and the 7 habits of kids and teens. The teens one is the best, it's outside his age range but will give you lots of tools. Oliver James' Love Bombing got a real pasting on MN, but it would be worth a try- 1:1 time focussing on him.
My elder son is becoming really quite naughty ( at home & school). He doesn't seem to respect any adults particularly, and seems to lack empathy. He's bright but rushes through his work and doesn't seem to care about what he's written as long he's finished first (he's very competitive). He wilfully (it seems) does the same thing we have asked him not to over & over again (like waking up his younger brother, early, each morning). It feels sometimes as though he thinks absolutely everything revolves around him. My 8 year old wakes early himself - between 4.30am & 6am (he's asleep by 8pm). His teacher has called us in 3 times this term because of "incidents" - disrupting class, being the joker, hurting others in group activities, being selfish.
We have shouted, reasoned, been quiet with disappointment, withdrawn privileges - everything. Obviously there are great things about him - he's loving, curious, clever, sociable, excitable - he's at his best often when he's alone with either just me or his Dad; but we'd very much appreciate advice on the wilful/disruptive behaviour please if you can help. Thankyou.