In 1990, in one of the most innovative developments in modern American education, the Milwaukee public schools created a parental choice system. Some low-income parents got vouchers that could be used to send their children to private schools.
It was a richly promising idea. The new option would let disadvantaged kids escape wretched public schools. Competition would force public schools to improve or close. Students would learn more.
Twenty years have passed. Last week, researchers at the School Choice Demonstration Project at the University of Arkansas published their latest assessment of the results.
What did they find? Something unexpected: Kids in the program do no better than everyone else. "At this point," said professor Patrick J. Wolf, "the voucher students are showing average rates of achievement gain similar to their public school peers."
This is a surprise to anyone who originally supported the voucher idea -- as I did. But it's entirely consistent with the record elsewhere.
In Washington, D.C., voucher kids improved a little in reading after three years, but not in math. A 2009 review of all the studies on voucher programs found few gains, "most of which are not statistically different from zero." This type of school choice, whatever its merits, has not accomplished what it was supposed to do.
In that, it resembles just about every idea offered by liberals, conservatives or anyone else in recent decades. Coming up with solutions for public education, it turns out, is easy. Coming up with solutions that actually work -- well, that's another story.
The latest trend in education reform is charter schools -- independent institutions that are publicly funded but free of the usual restrictions on hiring, firing, curriculum, instruction and so on. Today, there are some 4,700 charter schools enrolling 1.4 million kids.
Like vouchers, they are supposed to stimulate improvement by expanding options, fostering a rush to quality. Like vouchers, they have fallen way short of expectations.
In some places, there is evidence that students who win lotteries that let them go to charter schools do better than students who lose out. In New York City, Stanford University economist Caroline Hoxby found evidence that the charter school kids progress more rapidly than their peers in public schools.
Her study doesn't resolve why. Do the charter schools have better educational methods? Or do the kids just function better when surrounded by motivated kids (or kids with motivated parents)?