My nephew is 10 (nearly 11) and has been playing the bassoon for a year had has just started playing in his County Junior Orchestra. He was rather lost today because he hasn't the experience that the others have, which will come with time.
I've suggested that he might like to start listening to more 'classical' music just so that he starts to get a general knowledge and things start to become more familiar.
Apart from the obvious things like the Young Person's Guide to the Orchestra, what else would you suggest?