MCAT Improvement on the CARS comes down to two things
1) Natural reading comprehension skills: For some people the reason they don't do well is there reading comprehension skills are fine but they just can't figure out the MCAT logic, tricks, style and how they ask questions. This is rather learnable with the right commitment. For others, the issue just comes down to they struggle really grasping what they read, picking up on details, reading fast enough to have good retention and comprehension etc. This is where improvement can be alot harder to come by, particularly in a short period of time and where it is simply an issue of trying to maximize your abilities by learning everything you can about how the MCAT tests, the types of questions and tricks they like to pull etc and try and pick up on specific strategies that work for you( be it maybe skipping one passage and filling in random bubbles on the real deal to give you more time for the rest of the passages, focusing more on the first and last para, highlighting specific things in the passage, always re-reading the intro, making a rule that you will not spend more than 45 sec on a question etc)
2) How you actually review your practice passages: Doing MCAT passages themselves don't do that much to help you. Where you make improvement is making fewer mistakes. And the way to make fewer mistakes is to review all your mistakes and see what you did wrong, where your thought process was wrong, and what you can do to correct that line of reasoning and thought process. You'll find many like SN2 tell you need to spend 2-3X as long reviewing each passage as it takes you to do them. I would go a step further than that if you are struggling and really want to make gains; spend even more time. For a 9 minute passage, you might need to spend as much as 45 min reviewing it if you need to(I have). You really need to analyze every single thing. Here is how I went about it going through CARs/Verbal review
a) Analyze the questions; You need to consider multiple things here
i) why did the AAMC write them the way they did
ii) what was the AAMC trying to test you specifically on
iii) what were any tricks the AAMC tried to put in there or distractors to confuse you
iv) how do the answer choices differe
v) what makes a bad answer choice and what makes a good one
b) The text
i) read every sentence. Pay particular attention to the intro and conclusion. Why was everything put in there. What was the purpose of it? What did it tell you(and what did it not tell you is just as important)? How was it structured? How did the following paragraphs relate to it and what was its significance for the entire passage?
ii) now when you look at the questions see what parts of the passage did you need to be able to answer them. Just as importantly is what parts of the passages did you not need and what parts were designed to mislead you.
iii) What parts of the text are most important what parts are least. Where are unnecessary details that you don't need to focus on and specific phrases and even words that you do?
c) Themes
i) summarize each paragraph. What its purpose was. In particular summarize the intro and conclusion.
ii) what was the main theme: what parts of the passage did you need to answer this question about what the theme was. Again just as important as I keep saying is what parts of the passage can mislead you into thinking the theme was something it wasn't but that the AAMC asked to test you about ie the theme of the essay wasn't really about the purpose of the dollar bill rather than its legacy but one of the answer choices tests to see if you can distinguish these two.
iii) how much did specific aspects of writing such as quotes by figures, catchy phrases, anecdotes etc contribute to the passage and its overall theme. Were they distractors or where they particularly relevant?
Answer these things for every passage you do(especially those from the AAMC) and keep a log. If you are serious about improving your verbal score really do keep a log on a computer. It'll be long and tedious and suck. It'll feel unnecessary at times. But it's the type of thing that someone who is struggling should be willing to try. My own log on my computer of all the MCAT passages I ever did was over 200 pages. You will start to pick up on things you wouldn't otherwise. You will be able to compare the answers to these questions across many different passages and pick up on trends. You will start to see what makes a wrong and right answer and how the AAMC likes to trick you and what are things that trip you up. You can start to make plans to minimize the damage from your weaknesses. This brings me also to perhaps the most important part of all of this
Be willing to tinker and change your strategies to verbal if you are doing poorly, even if it means a complete overhaul and you questioning a lot of what you've done in the past when it comes to reading and analyzing text
Big improvement requires some kind of big change. Note there is no gurantee your big change will pay off at all but you at least have to give it your best effort. If it means reading a lot slower do it. If it means highlighting multiple phrases in a passage do it. If it means re-reading parts of a passage do it. If it means setting a timer so you don't spend more than 45 sec on a question do it. If it means reading aloud under your breath word by word even if you hate everything about that, then do it. If it means having to spend all the time it will take to do this and keep a log of it, do it. Because you can't really say you gave it your all in terms of trying to improve your CARs unless you really do every single thing effort wise to try and improve. And that involves going through a thorough review of each passage you do like this. The more you do it, the quicker you'll be at it and you'll realize what questions and issues I listed here you need to spend more and less time on and which you can essentially almost briefly look at and just skip. But you really need to be able to go through a thorough analysis and document all your analysis in some way. This is how you will be able to notice trends and really see what helps and doesn't help you. Tinker with different strategies; analyze everything the AAMC puts out there. They are giving you insight into how they think and these are the people who will write the test. It's a gift. Use it to your full potential you can.
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You'll notice this isn't something easily done in a couple weeks. It'll take a while, especially at first to really do this. If you have issue with reading comprehension, yes it can help to read dense work in other fields. No its not a high yield area of improvement and doesn't test MCAT skills directly, but it improves your fluidity in dense and uninteresting topics and allows you to have furhter practice with whatever strategies you come up with to attack passages. All that can matter.
Like I said above nothing will gurantee getting the score you want. CARs is built in a way so that everybody kind of has an intrinsic maximum score they can reach based off their natural ability. There is a point where practice and review has rather diminishing returns and can't make the difference you want. But your goal has to really be maximize every bit of ability and opportunity you have; particularly if your scores are poor and your reading abilities just aren't that great.
