There's an excellent sixth form college where I live that has supportive programmes for kids on the spectrum, preparing them for work, and helping with the transition. We're going for an interview and look round on the thirteenth... I'm really excited about it, since he'll have a support worker assigned to him, a chill out sensory area, and targetted work experience. The academics will be covered, but they're very practically oriented. He might even be given a work placement, so he goes into work a few times a week for the two years he's studying there. They have a lot of links to local industry, and most of their autistic spectrum students go on to get suitable employment. This could be just the transition he needs.