If you've tried AIS and ARISTA and gone to your teacher, it can be helpful to:
- Buy review books
- Talk to your Big Sibs who have taken those classes
- Visit https://stuyaristastudysheets.wordpress.com for some review sheets
That being said, ARISTA has been known to be extremely helpful, as has simply going to your teacher and asking for additional help after school -- most teachers are super helpful with stuff like that.
If you really feel like the grade you got was unfair, you can go to your teacher and contest it. Make sure you have a solid outline of the reasons you believe you deserve a better grade, including specific scores you received on exams, projects, etc. If your teacher agrees to the change, there may be a form they need to fill out, usually depending on how long it's been since the grade was given. If they tell you they need a form, or they don't know how to do it, just go to your guidance counselor -- they'll be able to help you from there.