I'm sorry to hear that you didn't get the grades you were anticipating. No worries, however! You should stay determined, because it's not entirely impossible to leap from your grades to an A*, though it may require a lot of effort and passion on your part. I have 4A*s and an A, Alhamdullilah. I'm a bad example to look up to because the reason I got A*s, imo, is sheer luck and my very quick grasping power and conceptual skills. I don't study a lot and have always been careless about my studies; the only edge I have is the fact that I remember concepts and ideas very well, Alhamdullilah and I can understand most things very quickly. I mean, I crammed the last three chapters of Physics in my head two days prior to the final exams
Nope, I had only borderline knowledge of them beforehand. BUT, one should never feel disadvantaged, because being hardworking is a much better virtue than being born intelligent. Here are some tips I can think of off the top of my head.
For
Biology, I've felt that a vast reading material never hurts. Albeit I only follow the
AS/A Level Biology (CIE) as the main guide. I've also referred to
Biological Science (a lot of detail, covers a vast variety of topics and concepts, a must-have),
Biology: Principles and Processes (not as much detail as Biological Science, but good for certain topics...you may or may not buy it) and
Advanced Biology: Principles and Applications (a very illustrious book, a lot of pictures so you can get a good idea about several processes/organs/etc, some topics are ONLY understood well from this book--a must-have but ONLY if you can afford a color version). These four books were more than enough for me--but handle with caution! I wasted a lot of my time in AS obsessing on these three reference books. I would've saved a lot of my time and maybe gotten a better UMS if I focused primarily on Mary Jones' book, as it is succinct and follows the syllabus/paper pattern. The other three books should be read
during the school year, as you try to understand and grasp concepts, so that you understand the topics very well. I'm not saying that you shouldn't take content from the books--you should, but for that, make some extra effort and make sure the latest syllabus is in front of you. If you're in doubt about something, whether it's worthy of memorizing or not, refer to the syllabus on the go and highlight the concepts/details that follow the syllabus. It seems tedious but if you do it as the school year proceeds, it won't even seem like an extra effort and in the end, you'll have a lot of good material to practice your past-papers from.
Also, you should watch videos on YouTube, particularly when dealing with mitosis/meiosis, genetic code, Mendelian genetics, biotechnology, gene technology and reproduction. These topics can be very well-understood and some seemingly tricky MCQs/questions dealt with in seconds if you
saw what was going on. I know teachers often draw illustrations on the whiteboard and our books have step-by-step illustrations of these processes, but seeing it happen in a movie has its own charm and its way easier to understand. Also, when I have trouble understand
anything, I 'YouTube' it. There are A LOT of Biology/Chemistry/Physics lectures out there, just make use of the internet and you'll see that you don't need to run to your teacher each time you're confused. This was a real help to me, especially when I studied Mendelian Genetics.
Lastly, since Biology is a theoretical subject, you may need to work on your expression and the content of your answers. MCQs were always easy for me but in the theory section, which is mostly what Biology is about, I found myself at loss of words a lot. A good technique, which a cousin of mine told me to follow, is to keep all your notes and books open in front of you when writing an answer. Refer to all of them and draft a very carefully thought-out answer. Yes, this sounds like hell! But you may not need to do it a lot, in fact maybe only once or twice each past-paper. Eventually, you will start to write in a similar, professional fashion and you will be much better at theory.
If you don't do this already, and if I haven't made this obvious enough yet,
SOLVE ALL YOUR PAPERS BY HAND. Don't 'think' of an answer, look at the modal answer/mark scheme and move on. A single past-paper solved by hand is worth ten past-papers solved by simply looking through them. I have done this since O-Levels and from my experience, I jumped two grades when I did past-papers in O-Levels--and in A-Levels, I jumped one grade. Past-papers are the best way to refine your knowledge and they are the most important assets CIE gives you. DO NOT WASTE THEM.
Anyway,
Chemistry now. I bought a lot of Chemistry books but ended up only using one book alone, AS/A Level Chemistry by Radcliffe. It's an older edition now, the new one is
Cambridge International AS and A Level Chemistry Coursebook with CD-ROM (CIE). I have not read the new one, but it covers the Chemistry applications and has two more authors than the previous one, plus it has positive reviews so you should probably get it ASAP. I tried following other books but in vain; my advice? Follow this book, and no other. Chemistry isn't as theoretical as Biology so you don't need a lot of details and expression skills. Instead, Chemistry requires a good grasping power and practice, especially when speaking of Organic Chemistry; you may just need to work really hard with little material.
Though I never did it, you can look up videos on YouTube for Chemistry too--though another thing you should do is find practice material for Chemistry. Old past-papers and Edexcel's past-papers work too, because you just need enough to contend yourself with. Another tip I used for Chemistry was, that for Organic Chemistry and Inorganic Chemistry, I made my own notes. I made flowcharts for reactions and tried to make the 'guides' as brief as possible, so I can have everything important from reaction intermediates, mechanisms to conditions in one place, and yet I can go through them in less than a minute. It was a really helpful technique, since I could simple my teacher's notes, the book and other documents into one and be fully certain of the answers to one-word Organic Chemistry and Inorganic Chemistry questions. Practice really pays off for Chemistry, and you don't need a book to refer to as you go through your past-papers.
As for
Physics, I am again a horrible example because I loathe the damn subject. I wish I could skewer it! I know I have an A* in it, but I'm not sure if it's because I was so obsessed with the subject because I did everything in my power to not study it and yet 'defeat' it. What I mean to say is, I took two Physics academies/tuition, one in my AS and the second after my AS exams (for A2). In my opinion, the first one was a fail and had no benefit while the latter proved to be a good choice in many ways. However, I hate Physics so unlike Chemistry and Biology where I can do most of the studying myself, in Physics I needed a tutor simply because I didn't want to study myself. I had an excellent Physics teacher at school, nonetheless, so when I say I never referred to a book for Physics, you must keep that in mind. His notes were the most resourceful, brief and compact morsels of information, and so I never felt the need to get me a Physics book. However, he referred his students to
Accessible Physics and
Pacific Physics 1 & 2. I did read the former and I think it has a good explanation of Physics in general, and helped me in my MCQ paper a bit just before I sat in it. The latter has very difficult questions, but the good thing is that if you can tackle such questions, A-Level Physics becomes a piece of cake for you--or so I've heard. I never bothered attempt the questions in Pacific Physics. However, I will recommend you practice lots of Physics papers. They were my savior, just as in Chemistry. Rote-learn the definitions if you have to because in every paper, they're easily worth 5-10 numbers. The key to Physics is a good Math and an even better formulaic reproducibility i.e. being able to comprehend and reproduce formulas wherever and however needed.
As for practicals, I'm going to let someone else who is fresh out of AS-Levels to guide you since it's been a year I attempted any practicals at all, and my component grades in the practicals were pretty bad: except an A in Chemistry, I had a C in Biology and a D in Physics. I haven't advised you on the applications a lot or paper 5 because you're yet to face them and they usually come to you at the very end of A Levels. If you want advice on them too, I can tell you some tips about those.
Anyhow, I hope this long essay was worth it! Best wishes in your A Levels. Do not be disillusioned by your grades; it helps to remember your priorities in life and working toward your goals with them clear in mind. My own friend had 1A, 2Bs and a C in her AS-Levels and pushed it to 2A*s and 2As when she repeated her AS-Levels with A2. Conversely, a friend of mine had 4As in her AS-Levels: 99 in Math, 95 in Chemistry and Biology, 93 in Physics. In her A-Levels, she dropped them to 1A* (in Math) and 3As. Similarly, a friend with 3As above 90 and an A below 90 in AS found herself thunderstruck in her A-Levels with 3As and a B; all her grades dropped by one step. So, life is full of surprises--be prepared and strive for what you want. <3