The worst parts about my son are he can be boisterous and big headed, he is a little too aware and proud of being top of the class.
I've skim read the rest of the thread but maybe this is a good point to mention to him that if he is saying unkind things to other children and showing off, then this is the result: he wont have any friends.
I dont think it is nasty to exclude him. If he really is boasting the whole time and making the other children feel bad, why should he be invited?
You might also want to tell him that he might not always be the top of the class. I wasnt that bright at primary school. But I think maybe alot of it was lack of confidence maybe from DC like your son who boasted about themselves the whole time
I was no good at maths, not great at spelling, blah blah.
I really blossomed when I was older, became more confident in myself.
Well now, I'm a solicitor and lots of the big headed kids didnt do as well.
Pride often comes before a fall.