If he gets through all seven then he is incredibly determined.
I would beg to differ. The PPL exams are very easy - especially for someone of a young age who is at school and in a learning environment. Add to that all the confuser guides and really there ain't much to it.
If he is serious about it, suggest working at the local aero club at weekends in return for lessons. If he hangs about a lot he will meet a wide variety of people, all ready to give him advice. He will be able to go along on flights if anyone has a spare seat and he is friendly and outgoing. Washing airplanes for people is another way to get in. In short immerse himself in aviation in his spare time - he'll either love it or hate it. IMHO the kids I see at aero clubs who get involved are much happier and 'into' their aviation than those who come and go just for their lessons.