From AMSP have a look at this great new magazine which is aimed at high-attaining Year 12 (UK age 16-17) students. You can read more about the magazine and freely access the first issue here.
You will find out more about where Maths can take you in the future, learn more about the applications process and what it is like to study maths at university.
Of course check the Do some maths! section. There is some great advice on problem solving and puzzles to try.