Beginning 40 years ago, a series of court rulings forced states to reallocate money for education, giving more to schools in poor neighborhoods with less in the way of local resources. Critics such as Eric Hanushek, an economist at the Hoover Institution, argued these decisions were simply "throwing money at schools." His research found that there was little correlation between how much schools spent and how well their students performed on tests.

It's a view still held by many politicians today, including Gov. Andrew Cuomo (D-N.Y.). "We spend more than any other state in the country," he said a year ago. "It ain't about the money. It's about how you spend it -- and the results."

More recent research, however, has found that when schools have more money, they are able to give their students a better education. A new study on those who went to school during the school-finance cases a few decades ago found that those who attended districts that were affected by the rulings were more likely to stay in school through high school and college and are making more money today.

The authors, Kirabo Jackson and Claudia Persico of Northwestern University and Rucker Johnson of the University of California, Berkeley, released a revised draft of their as-yet-unpublished paper this week. The benefits were most obvious for students from poor families. They found that a 10 percent increase in the money available for each low-income student resulted in a 9.5 percent increase in students' earnings as adults. A public investment in schools, they wrote, returned 8.9 percent annually for a typical pupil who started kindergarten in 1980.

The findings are evidence that public schooling can be a way for children who grow up in poverty to overcome their circumstances, Johnson argued.

(Read more at the Washington Post).