It is wrongheaded and unproductive to judge schools by the family backgrounds of the students, but we all do it.
Whenever I interview people around the country about their local schools, they tend to praise those where most of the students are affluent and criticize those where most are poor. Having a large number of black or Hispanic students will also hurt a school's reputation, but in most cases, such schools also have a majority of children whose parents never went to college and don't make much money. It is class, not race, that makes the big difference.
Children from low-income families have a disadvantage. On average, they don't get the same opportunities to learn in their early years that affluent children do. It is difficult to catch up when you start far behind. That reduces the average test scores of the schools they attend.
Wouldn't it be wonderful if our state legislature and governor would have some kind of epiphany similar to Matthews' comments that would lead them to solve Michigan's school funding inequities?