When I was in school I had a bus ride of 45 mins either way from school, I used to read my subject book from start to finish every day. (every day I'd pick a different subject or one I needed to improve) I had A+ in all my classes.
Try the read it a few times to get more out of it for studying.
Read over your class notes from the beginning of the semester to the current day, every night. Answer all of the questions at the end of each chapter and read over those answers, too.