You're sort of not allowed to mention culture in the context of education. Otherwise people might realize that different cultural groups have very divergent education outcomes. For example, Asian students study 2x as much as white students and 3x as much as black students. It is likely not unrelated that Asian students have much better educational outcomes, regardless of class. For example, Asian students whose parents have no HS degree perform better on the SAT than black students whose parents have a doctoral degree.