our ds arrived new to area last year and had real difficulties breaking in. a year on, looking back, as he now is part of a large group:
-minecraft; fifa 14;
- xbox multiplayer was an easy way to link with people but in his home where he felt safe;
he tried lunchtime clubs and the library but that worked less well for him;
pushing himself to go to the local park, and to join the groups there even though it wasn't very acceptable to go alone, this has been the thing which made the big difference for him - he said recently, in school everyone was in closed groups, it is easier to break in in the park.
what i wish i'd known: his school has a pupil inclusion unit - a special classroom open to kids who are struggling. you need to be referred and can go with a friend, but it gives a safe base if you are shy. none of the teachers ever mentioned it, but getting a referral did help him feel he would have somewhere to retreat to, and once referred he never went.
reassure your ds lots of kids are faking it. we watched the itv series faking it online - the surfer episode, so ds could see about body language. our gp said she was seeing some 10% of year 7 boys for anxiety issues - so he isn't alone and will find others.
good luck to you and him.