So I'll preface this by saying that I haven't actually received a score on the real MCAT yet (took in in April but only because it was half price, just for practice and voided it).
However, I've been getting 512-515 on all of the TPR and Kaplan exams (lowest is 512) I've taken in the past 2 weeks (4 of them), which I'm assuming puts me in a decent place.
I've been studying for 5 weeks so far, and when I first started I was getting only about 50-60% right on CARS if that; my average was 55% right per section (took a few of the old AAMC practices).
So now my CARS average for the actual full length practice exams is consistently 80-90%; hoping to bring it up to 95%+ consistently before September rolls around; but here's what I did.
1. If you're like me, you're very used to reading things passively. You read it but it just goes in and out. I think this is a by product of the schooling system where memorizing plays a huge part in getting the A. So, what I started to do is fall in love with what I'm reading, in a way. I read it out-loud, very quietly, and in a funny voice in my head that entertains me. I look at it like a game now. Every time I see a passage I smile and just make it fun!
I'm like you in that I don't highlight and just read the passage once over, occasionally going back for a quick skim of the paragraphs the questions reference me to.
Think about it like this, when you read an article/book that you LOVE, do you remember everything in it? Of course you do!
For me, now its bodybuilding/powerlifting. I've been powerlifting for years now and I still love it. Every time I read an article having to do with some new training style I might be researching, or about testosterone, igf-1, all these various molecules that play a role in the body, maintenance of body fat, muscle growth pathways, nervous system -- literally anything that relates to training, I can tell you word-for-word what that article said immediately after reading it. Why? Because I was PASSIONATE about what I was reading. I was truly interested.
You CAN learn to treat the MCAT CARS section this way. I know because I did it in only 5 weeks.
So tip 1; learn to treat the MCAT CARS like that amazing book you've been wanting to read or an article about something that absolutely infatuates you.
2. The ability to consistently apply this mindset to MCAT CARS passages comes with practice. So does getting better at answering the questions themselves, and reading quickly. When I started studying 5 weeks ago I had done zero practice passages. Now I've done a total of 4 Full-lengths, a few old AAMC exams, and all the EK questions in their new book set, and you can bet it is just SO much easier to answer MCAT style questions; it's literally becoming second nature.
MASS PRACTICE is the second key. There are plenty of ways to do it for free/very cheap, so money should not be a limiting factor here.
CARS is a skill that can be developed just like anything else -- and don't let anyone tell you differently, because they are lying. In fact, getting an amazing score on the MCAT is something that can be learned 100% in my opinion.
3. It is my opinion that it is a waste of time and resources to write things down on CARS. Most questions I've seen can be answered without having to memorize tiny details; and if you truly can slip into the mindset of reading the passages passionately and with a genuine interest, you'll probably remember the little things anyways.
So that's my advice hope it helps a bit and possibly motivates you