As far as actual grades, 90% and above = A = 4 80–89% = B = 3 70–79% = C = 2 60–69% = D = 1 59% and below = F = 0 For each class you get a grade. That grade corresponds to a 0–4 number. They average those numbers and you get your GPA. So say you have 5 classes. You get 2 Cs, 1 B, and 2 As. 4 + 4 + 3 + 2 + 2 = 15. 15/5classes = 3. Your GPA is 3.0.