If you aren't happy with your grade, you can always ask your teacher for some help. Teachers are there to help students, so they're there for you whenever you need them. You could set up study sessions with your teacher. If you don't want to study with your teacher, try to look at your studying methods. Do you take good notes? Do you look at said notes after class? Are you turning in papers on time? If you study enough and put your mind to it, you can probably get an A by the end of the quarter.