Lots of reasons why some students excel in math, including natural ability, family support and willingness of the students to do the work. The only rational approach to the issue is to reward achievement regardless of the demographic irrelevancies.
the very same math (calculus) that is performed on paper in physics and such are performed in (slow “learners”)their heads while on the football field and basketball court;distance, velocity and acceleration of the the ball and persons, requires differentiation and integration. They run away from in the classroom and to it on field and court.
Math is not a natural language, like English, Spanglish and Ebonics, that children can pick up through social interaction. Math needs to be learned and requires daily effort and yes, lots of homework. You can't pick up the math book for the first time the night before a big exam and expect to do well.