Are there any other materials out there similar to the introductory chapter of "The Unwritten Rules of Friendship"?
Although DS2 is coming up to 8, I still think there is scope to help him in his peer interactions, just by telling him the rules - but I need to see those rules preferably in developmental order - rather as I used to see the rules of receptive language development.
for instance, the other day, I asked him to tell a neighbour's young daughter something, and he said he wouldn't go alone "because I'm scared of mini-kids". He does indeed ignore these little girls.
I told him that when you see a mini-kid you should do four things: (i) look at their eyes (ii) say hi and wave (iii) smile and (iv) nothing else - you're done - it's their turn now. He seemed to find it a great relief to be told what he was supposed to do and practised it with some success.
I remember in Unwritten Rules learning such gems as not marching up to other children and say "can I play?" - instead edge into the game by returning a ball and wait for an invitation.
DS2 is ready to learn about things like situations where it is appropriate to correct other children (the classroom where we are talking about things we are learning, or if you are invited to join in a game that would hurt other people) and situations where it is just not necessary to correct and will only annoy others.