https://www.sciencedirect.com/science/article/abs/pii/S02765...
Just one example of many.
Everybody's talking about the problems with schools, but the issue is the enormous gap in economic inequality that is just growing larger and larger. Parents who have to work 2-3 jobs to support their families don't have the time or energy to devote to supporting their children in their academic lives.
Teaching at the rural school I grew up in really changed my perspective. I was very abnormal when growing up there, and all my friends were too (I can only think of one good friend who's parents were divorced, and her mom and remarried when she was fairly young), and I was super insulated from the realities of things there. Coming back as a teacher made me see how much worse it is, and it's a clear difference between the kids; even those kids whose parents want them to do well struggle if the parents can't be at home.