One thing that really can help someone on the spectrum (mainly aspergers) actually do something and hold the potential for them to learn social skills is with board games. Board games often require human communication. When you practice communicating you become better at it. The best is if the child gets into it then you can really get some good growth out of them.
Some favorite games of mine are:
Apples to Apples
Settlers of Catan (hint if a child likes it and other kids around like it you can get the 5-6 player expansion pack)
5 second rule
There are many more out there, and as always with Bringing it to them know what game may