How do I help/prepare DS for group play situations?

d.f

How do I help/prepare DS for group play situations?

He's fantastic in one on one or small groups (less than 4 kids). However, when the groups get larger and/or more structured play that is not adult facilitated (tag, hide and seek, made up games) is introduced he struggles.  He kind of follows the group around but is unable to interject himself or keep up with the pace of the changes.  I also noticed today he was falling back on scripts (introducing himself and spelling his name repeatedly) to the point where at least one other child ( a few years older) was getting annoyed.

Once he left the group and started playing with one other kid in the sand he was in his element.  He was maintaining a back and forth convo  (with the similar aged kid he just met!). He was sharing his sand toys and cooperatively building a sand castle.

The differences between the two play situations were pretty stark. 

He's currently in a group speech class but his SLP is talking about bumping him up to a Social Skills group this Summer. 

Any ideas on how I can help him in the mean time?  He's starting to notice rejection and when he's on the periphery of a group.   He desperately wants to join in but currently  doesn't have the skill to do so.  How do I teach those skills? Heck what are those skills?

Thanks! 

d.f

Thank you for your response and sharing your knowledge.  I really appreciate it! 

Short answer? Years and years of social skills instruction with ample opportunities to practice emerging skills.</span