Maryland's Test Case to Close the Achievement Gap

In recent years, at least 70 districts have experimented with mixing low-income children into more-affluent classrooms. But with savvy parents volunteering their kids, it has been hard to draw larger conclusions about the success of these efforts. That’s not the case in Montgomery County, Md., where local zoning laws required affordable housing amid the tonier homes of Washington commuters.

The Century Foundation, a progressive think tank, tracked two groups of low-income children: those randomly assigned to higher-income schools and those not. The study, released last month, showed that between 2001 and 2007 the kids sharing air with the wealthy cut their achievement gap by almost a third in reading and half in math—even though the lower-income schools had more funding. The difference, says author Heather Schwartz, comes down to environment: fewer disciplinary interruptions, more engaged students, and a stable set of teachers. Money still matters. People, it seems, just matter more.