In reply to Groundhog:
As Marks suggests, Kids club is an option. But he might be too old and experienced for that now.
What is the bouldering like? My son, when he got to that age, preferred to boulder and met other keen teenagers that way, who he now goes to the crags with bouldering and sport climbing. If the bouldering isn't great, perhaps try a dedicated bouldering wall occasionally.
If he finds some other keen kids his age he gets on with, they'll prefer to arrange to climb together themselves using one of those black box things they all seem to carry these days.
Post edited at 09:27