Just keep practicing past papers

Review and study. Start early. Do practice tests. There are several sites that go over all the same material you'd be doing, check them out and if one doesn't make sense, check out another.

For a lot of people (I can't speak for you, but this is what I find) nothing in math by itself is very hard when explained well. It's just not always explained well, particularly in when to use things or what makes them different from everything else, which would make all the different things you learn a lot more manageable. And usually if you google whatever it is you need to know, a few different things on the first page will tell you it. And if (from being good at computer science and physics) you're more of a hands-on learner, that's generally a much better way of learning in the first place.

I don't really know all the details of education in the UK, but worst case scenario there should be options available to you. They usually won't get you in immediately after secondary school, but I'd say that's not as necessary as a lot of people make it out to be. Though I know even just explaining the situation and what you've done to get better can help a fair bit in some places (I got in my university without meeting the physics requirement, because I was in a situation where I could only take the first high-school physics course and not the continuation, for example), though I can't say the same about everywhere and I'm certainly not in the Ivy League either. But if you're committed to working hard at math, it shouldn't have to come to any of that.

You could always try getting a tutor for maths, although I don't know how much time left you have before your exams and whether that would be a viable option.
Also, I'm not sure if you actually need maths to study computer science at university? A few friends at my uni doing computer science didn't do maths, but you probably know more about that than me. If the worst comes to the worst, you could always take a foundation year too, which is a very popular option and pretty much guarantees you doing a degree in your chosen subject.

I was in bottom set Maths during my GCSEs but still managed to get an A in Maths. Honestly the best thing to do is to just find as many past/specimen papers as possible and do them. I'm not sure if the new GCSEs have been implemented yet (so the paper structure might be different), but it's really important to make sure you don't drop any marks on the easier/earlier questions.

Just do enough past papers so that you're comfortable with the time and layout, good luck :)

Do past papers. A lot of them. It is the best way to revise maths. BUT don't do the latest papers first. I'd work from oldest to newest, whilst keeping from, say 2015 onwards, for the weeks leading up to the exam. If you want, you can add me if you have any questions, I'm about to take my further maths exams (all the core modules + S1 and M1) so I'd say im pretty good at maths, and I know the style of questions and stuff.

I'm not sure how it works in UK but I'm a math major going into the software industry (CS and music minors). Comp Sci is a unique field in that a lot of the things you end up doing in the field (software, web dev, etc.) are all learnable outside of class, and you can have a hefty portfolio and CV without even taking a substantial amount of CS courses. I've definitely missed out on some internship opportunities because I'm not an actual CS major, but I've also gotten interviews with top tech companies like Twitter and Amazon for Software Dev openings.

On the note of subject matter, do be aware that the overlap between physics and CS isn't actually that great. I thought it would be going into college (I was a planned CS/Physics double major), but it would've taken me extra time to graduate because they are both credit intensive majors at my university. Math is definitely important algorithmically for CS, but for the most part not too necessary after a few calculus courses, unless you're going into financial tech. Fields like quantitative finance or the fintech industry will naturally be much heavier than pure web dev or software.

So while I can't give you advice on how to do well for your strange British tests, I can definitely give you some scholastic and career advice as a dude a couple years down the line who's taken the courses you want to and is applying for internships currently. Drop me a PM or something if you'd like; good luck on your studies.

based on what? Have you written nontrivial programs? I think you would find that by creating things you will pick up the math foundation required by CS programs. Programming has a very low barrier of entry, just install a linux distro and start writing simple C programs in vim. If that doesn't interest you, then I can't see why you would want to work in CS.

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If you cannot achieve the grades necessary, and you fail your exam. Don't worry about it. Get a job, resit gcse's and come back next year better prepared.

Failing an exam is not the be all end all of life. Even though school makes you feel that way (mine did at least).

Of course, passing exams first time is best. You basically put your life on hold for a year if you fail.

Also check with your school admin, some exams may not be re-takeable. Sometimes failing is the end of that specific course.

Advice for how to pass maths exams is practice the questions. I was always good at maths, but a friend of mine wasn't. He sat and went through the entire syllabus learning all the main points, and turned his C to an A. In other words, he sat down and did the work.

Best of luck!

take it from me, don't take physics unless you're a god at it. I found out after I took it that you don't need it and you'd be way better off doing a different logical subject like further maths.

honestly do past papers, also if you payed attention in lessons then you can coast off of what you remember in lessons (though lessons may have ended for you). if you do that and a ton of past papers it becomes really easy to get a good grade and not very stressful because you know you will do well.

Don't worry about not getting the grades to do Comp Sci at uni, I beefed my A levels hard, went back to college a few years layer and took a Level 3 Diploma in Software Engineering that I'm about to finish roughly around now and its the equivalent of 3 A* at A Level, with about 20% of the work load compared to going to Sixth Form and doing Mathematics, Computer and Chemistry which is what I was doing before.

Got my offer from Cardiff Uni for comp sci earlier in the year (which I'm deferring for casting). But yeah, I really wish someone had told me all this at the time otherwise I wouldn't have wasted two years of my life at Sixth Form.

Command line and scripts are some tools that allow you to write useful programs. The goal of CS programs is to get people to a state where they can build useful things, unless it is heavily focused on theory, in which it's much more about creating people who can talk about and apply abstract ideas of computation, but not actually make anything. Three raspberry pi's is a lot, have you written anything for them (not just installing / configuring other people's software)?

The point I was getting at is that much of the math required by CS programs is picked up while writing code, and I think you'll find that after creating programs that the math exams become much easier. In addition, most CS programs are geared towards making the average person an employable programmer, which is done thru making them write nontrivial programs. This can easily be done on your own time if you're motivated and able to think of things to do.

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If you're confident in your ability to code then why worry about a math exam, go apply for internships. Companies are always looking for people who can program well. Hopefully you're using some sort of version control / github so potential employers can see that you've actually done things.

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