Here's a brief run down of what happened to me.
I started doing my GCSEs when the government changed from the letter grading system to the numeric system (A-U, 1 - 9). I was predicted to get a grade 6 in Maths but could have probably gotten higher. For some insane reason the head of Maths at my high school decided that everyone apart from the top set was going to sit foundation Maths even though the lower level staff pleaded for him to change his mind. I ended up passing all my GCSEs and getting a grade 5 in Maths which is the highest available on foundation Maths.
I wanted to do further Maths at A-Level but couldn't because I only had a grade 5 so I ended up getting doing an extended UAL level 3 game design diploma where I achieved a distinction. I told one of my tutors about the problem in the second year of the course and he got in touch with the Maths department to help me do what I actually wanted to do (according to him I was far more skilled at programming than what he'd expect at my age and thought my talent would be wasted in game design). I talked to the Maths department slowly over a few months and eventually find out that I'll have to sit higher GCSE Maths for a year which I'm fine with. They asked for my email and told me they would email me when they have more information about the cost and when I should go in to enroll but today I found out by accident (not from them) that my college isn't doing a higher GCSE Maths course this year. It's now too late to try to get in to uni, I can't do the A-Levels I need to do what I want to do at uni because of the Maths, and everywhere I look online to sit higher GCSE Maths is either on the other side of the country, don't accept people my age, or only do a foundation Maths course.
Can anyone who has had a similar experience give me any advice? I want to do computer science but I want to do a one that involves a lot of Maths rather than just "Hey look this is an array, it does cool stuff, it's basically a pointer but you don't have to manually figure out offsets". I've thought about sitting the exam as a private candidate but I'm finding it hard to find anywhere near me that will allow me to (I live in Newcastle upon Tyne if anyone knows anywhere near me) and I'm worried that I won't be able to learn all of the required content without guidance.
One other thing that's slightly related. Does anyone know if brilliant.org would help with either GCSE or A-Level Maths? I've been tempted to buy it for a while but I'm not sure how much more helpful it will be over Khan academy.