In reply to cleghm01:
The Peak can be a great place for an introduction to trad climbing and there are plenty of instructors over there to guide you about. Alternatively you may think about North Wales, depending on your son's ambition. He may be more inspired by the mountain setting in Wales, being able to see larger peaks etc. and seeing where trad may take you. Equally there are plenty of instructors around North Wales who can help you out (including me).
Drop me a message if you would like any specific info