She is one year advanced in math compared to the normal high school sequence (which leads to precalculus in 12th grade), although AB will only lead to being one semester advanced in college. There may be math superstars in her high school, but try not to think of them as typical students who go into computer science or other majors that use math.
Computer science mostly depends on the ability to think logically, which is similar to how one thinks in math, even though it may not use the usual types of math directly as much.