Have you considering finding a tutor? One of the math teachers at your high school is bound to be able to tutor you in stats (even if they don't officially teach it). If not, perhaps you (or your mom) can contact the local community college and see if you could hire a college student who may be majoring in math to tutor you.

Since it's an online class you are essentially teaching yourself...perhaps it's just a matter of having someone teach it to you first-as that's how you probably learned the other types of math you've already taken.