“When researchers control for the effect of poverty, American students score near the top of the world on international tests. Our overall scores are unspectacular because of our unacceptably high child poverty rate, now around 25%. The problem is poverty, not teacher quality. Poverty means food deprivation, lack of health care, and lack of access to books. Each of these has a strong negative influence on school performance.”

Source: Schools Matter: It’s poverty, not teacher quality