Hi
If you are looking at maths, it might be worth looking at a stats gcse too (if such a thing exists!).
We have just started a 15 wk stats unit (the longest individual uni on the course) on our Access to HE (Science) course and lots of people are really struggling with it.
According to our tutor, Stats is a compulsory part of any Access course and is also taught on almost every 1st year university course.
If I had known this was coming, I would have done more advanced maths to prepare for it as it is pretty hard going.
Hope this helps and good luck.
Kate