Most people never are taught how to study, so we tend to come up with whatever “makes sense” to us–usually things that aren’t effective (like rereading and highlighting). Although it can feel scary and difficult to try a new technique, if you never take the chance you won’t know if there is a better way for you to be studying. Try using retrieval practice, spaced practice, and elaboration and your grades will likely improve quite a bit.
DD uses Quizlet religiously. You can make your own flash cards, find good sets already done, or do them with friends in the class. READ the math book: raised D1’s grade a full letter grade almost immediately. Sit toward the front of the class and ask questions. Talk to the teacher privately if you are struggling: they love it. Make sure you are clear on material before leaving class to save time: if you don’t get it, other people don’t get it either. Email the teacher with questions on how to do homework if confused. in a word, be an active learner…not a passive absorber.
Read one chapter ahead in your books all the time. That way you have a general idea of what the next chapter is about. Don’t make math about memorization-- actually learn the material and do the same homework page twice (once for practice, second for understanding).
I second the sitting at the front thing. I’ve noticed that when I choose seats at the front I focus a lot better and ask more questions which betters my understanding, which then translates to better test scores and grades.
When a teacher stays after school to help, TAKE THE OPPORTUNITY! It will give you a better relationship with the teacher (which might help you like the class more) and they want to help you! Even if you understand the material for the most part, go in and make sure you understand it fully.
Use notecards religiously (esp. for history or similar) and watch tons of videos on subjects. Khan Academy has videos on almost every subject. If it’s about math, I’ve found that a girl on youtube (her channel is called MathBFF I believe) is REALLY good at teaching the subjects. I’m in AP calc right now and I just watched a video on derivatives last night. I pretty much understand them perfectly now. Take advantage of the technology you have around you because it really works wonders. I will be using videos for all of my science and physics needs this year (and into college for sure)