Give the lad a break!
Although I agree with some of the earlier sage postings, I myself am more wisdomous and tolerant. Try searching 'psychometric tests for pilots' in google. There are tests one can buy and ones for free. GAPAN also sell a good course. If your idea is to try and practice you might want to think twice, most people are adamant that one can't get better at these tests by practice (as an earlier post said, they look for improvement, not immediate greatness).
My advice is to concentrate more on your C.V, join the cadets, get a PPL and your A-levels, do DofE and travel, you're more likely to get rejected for being found wanting in depth and breadth of experience than in aptitude.