As others have suggested, try gliding.
I certainly think it is more fun than flying a light aircraft (0-60kt in 4s, mandatory aerobatics before you can go solo at 16, and much more), and it is much cheaper. Cost? Likely to be, say, £600 to go solo on some type of a fixed-price-to-solo scheme, then £100/year, £6 per launch and £20 per hour).
Find your local club via
www.gliding.co.uk
Of course, you should make sure that you aren't distracted from your schoolwork either by flying or girls[1], since flying might not turn out to be The Right Thing for you.
[1] ever worse would be the combination of the two; at my club there are two pre-solo 16/17yo girls.