In 1962, the year before the March on Washington, about half of all white people over 25 had completed high school but only a quarter of blacks had. Since then, that gap has been nearly erased, shrinking down to about 3 percentage points, but the gap in college completion rates has widened. And for most families, college is the ticket to a middle-class life, improving economic mobility for children and protecting families from financial distress.

Only 4 percent of blacks age 25 or older in 1962 had a college degree, while 10 percent of whites did. In 2012, 21 percent of blacks had a college degree and 31 percent of whites did, meaning the gap grew from 6 percentage points to 10 percentage points.

Differences in school quality add up over time

The quality of public education also differs by race because of our school financing system. Because of the black-white wealth gap, richer white families live in school districts with greater property tax revenue supporting higher education spending. Differences in early education opportunities add up over the school career and result in large achievement gaps. Taking family income and neighborhood characteristics into account greatly reduces the black-white achievement gap, suggesting that family income differences drive much of the achievement gap.

Policies aimed at closing the education gap are in jeopardy

Higher education has long been the vehicle for children from lower-income families to move up into the middle class. Children of less-educated parents are more likely to be held back, and tend to have less education, lower lifetime earnings and wealth, and worse health.

In the recent recession, families with a college-educated worker were much less likely to suffer from job loss. Families with more education tend to be less likely to suffer large losses of income as well. So not only do families with more education have higher lifetime incomes on average, they also suffer less risk when it comes to their incomes.

The persistent gap in higher education between blacks and whites—largely due to persistent wealth differences—leads to lower income, wealth, and health in future years and in the next generation. The gap in college completion is actually larger today than it was 50 years ago, and many of the policies used to close the gap are under fire, including admissions policies and financial aid.

We need new policies, and intervening at the end of high school may be too late: we need to address racial disparities that begin at early ages and may be driven by large differences in the quality of public education.