Does free community college work? An experiment in Chicago suggests that the answer is yes. Two years ago, under a program called the Star Scholarship, Chicago began to offer free community college to all public high school graduates who earned a B average or higher and demonstrated near college-level proficiency in their work.

Since the program was created by Mayor Rahm Emanuel, roughly 1,000 students a year — about 5 percent of each Chicago Public Schools graduating class — have claimed their reward...The early results of this initiative have been incredibly encouraging.