I know, because admirers of Barack Obama tell me, that this year's election poses a choice between a candidate who represents a fresh approach to problems and one who offers a dreary continuation of the status quo. That much I understand. What I sometimes have trouble keeping straight is which candidate is which.

On the subject of elementary and secondary education, the two seem to have gotten their roles completely mixed up. Obama is the staunch defender of the existing public school monopoly, and he's allergic to anything that subverts it. John McCain, on the other hand, went before the NAACP last week to argue for something new and daring.

That something is to facilitate greater parental choice in education. McCain wants to expand a Washington, D.C. program that provides federally funded scholarships so poor students can attend private schools. More than 7,000 kids, he reported, have applied for these vouchers, but only 1,900 can be accommodated.

Obama promptly expressed disdain for McCain's proposal. The Republican, his campaign said, offered "recycled bromides" that would "undermine our public schools."

You would think a leader who plans to liberate us from the partisan dogmas of the past would be open to this approach — and in February, Obama indicated he was. "If there was any argument for vouchers, it was, 'Let's see if the experiment works,'" he said. "And if it does, whatever my preconception, you do what's best for the kids."

But it didn't last. After those comments drew attention, his campaign hastily reminded voters that "throughout his career, he has voted against voucher proposals" and that his education plan "does not include vouchers, in any shape or form."

Too bad, because vouchers, though they have been tried only in a few places, have shown considerable promise. Patrick Wolf, a University of Arkansas education professor who has the job of evaluating the Washington program, says that of the 10 studies of existing voucher programs, nine found significant achievement gains.

In Washington, it's too early to tell if test scores will improve. But already, Wolf's report says it has had "a positive impact on parent satisfaction and perceptions of school safety."

Those benefits ought to be enough to make Obama reexamine his preconceptions. After all, it's not as though everything else we've been doing has set the world on fire.

Since the passage of the No Child Left Behind Act in 2001, the nation has seen no improvement worth mentioning. As Andrew Coulson of the Cato Institute writes, "U.S. students have suffered overall stagnation or decline in math, reading and science in the years since NCLB was passed."

Democrats don't like NCLB, as a rule, but about the only thing Obama and his party offer is pouring more money into schools and teacher salaries. It's an idea that sounds sensible not only to teachers and principals but to a lot of other Americans as well — mainly because most taxpayers don't realize how much they are already spending.

A survey by William Howell of the University of Chicago and Martin West of Brown University found that 96 percent of Americans underestimate these expenditures, usually by a lot. On average, per-student outlays are more than twice what most people think, and teachers get $14,370 more per year than commonly assumed. Per-pupil spending, adjusted for inflation, has soared in the last four decades with no visible payoff.

Vouchers are a different approach: Instead of enlarging the monopoly, stimulate competition by empowering low-income students and parents to go outside the public school system. Over time, that should give rise to more private schools and impel public ones to do a better job — or, in the case of the worst ones, close down.

It's not a radical design. It's pretty much the model we use for higher education, and it may explain why American universities are held in much higher regard around the world than our elementary and secondary schools. And it's comparable to what we use for most other goods, which accounts for the vast improvements in computers, cars and TVs that have occurred even as public schools were stagnating.

McCain apparently grasps all this, while his opponent prefers to close his eyes. Obama says he stands for "change we can believe in." But change that works? That's another matter.

Steve Chapman blogs daily at newsblogs.chicagotribune.com/steve_chapman. To find out more about Steve Chapman, and read features by other Creators Syndicate writers and cartoonists, visit the Creators Syndicate website at www.creators.com.

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