I knew (second hand) a teacher in a rural area of a low population state. All white kids, she'd have kindergartners cussing her out. Very little hope for any academic future for the other grades as things didn't get better with the older kids.
I knew a white kid who lived in a trailer park whose mom was upset he was getting tutoring after school for his dyslexia because she told him he'd never amount to anything.
My mixed race friend mentioned he was accused of "acting white" in school because he actually tried to get good grades.
What do all of those things have in common? Poverty, yes, but blended with hopelessness. The kids were surrounded by people who didn't have much, didn't think they'd get anywhere, and didn't believe the kids would ever have a chance at a better life.
That last part is what separates them from kids in third world countries who still manage to achieve academic success. Hope and optimism aren't guarantees; they aren't a replacement for social support. They are, however, a necessary ingredient for the intrinsic motivation necessary for personal growth.