I'm pretty much in the same boat as you. I'm 16, have picked my A-Levels and I want to go on and do a CS degree at a Russell Group university. I've picked Maths, Physics, Economics and Chemistry. Chemistry is pretty much irrelevant to CS, I just picked it because I'm good at it and Economics is there because I'm interested in it and it's a more laid back subject (compared to maths/science). The most important ones there are Maths and Physics, I'm sure that both of these are popular choices among CS applicants and I know that Universities regard them as some of the harder A-Levels you can pick.
If you are still able to change or pick your A-Levels I'd recommend doing further maths. From what I've heard from other people doing CS, some of the first year is similar if not the same as A-Level Further Maths so knowing it in advance could reduce some of your uni workload. Unfortunately I can't change my options now but I might be able to drop Economics for A2 and pick up AS Further Maths if my AS Maths results are good enough. Don't be put off by the difficulty of Further Maths, good things rarely come easy in life!
According to the Guardians League table, people who attend the top uni's and take IT/Computer Science usually have around a 70-85%* chance at getting a job within 6 moths, so it's not all bad. If you come out from uni with decent grades you shouldn't have much trouble finding a job, especially if you get a 1st or 2:1 from a decent uni like Imperial or Oxbridge.
Any Idea where you might want to go for uni?
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