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单选题The richest man in America stepped to the podium and declared war on the nation's school systems. High schools had become "obsolete" and were "limiting—even ruining—the lives of millions of Americans every year. " The situation had become "almost shameful. " Bill Gates, prep-school grad and college dropout, had come before the National Governors Association seeking converts to his plan to do something about it—a plan he would back with $ 2 billion of his own cash. Gates's speech, in February 2005, was a signature moment in what has become a decade-long campaign to improve test scores and graduation rates, waged by a loose alliance of wealthy CEOs who arrived with no particular background in education policy—a fact that has led critics to dismiss them as "the billionaire boys' club. " Their bets on poor urban schools have been as big as their egos and their bank accounts. Has this big money made the big impact that they—as well as teachers, administrators, parents, and students—hoped for? The results, though mixed, are dispiriting proof that money alone can't repair the desperate state of urban education. For all the millions spent on reforms, nine of the 10 school districts studied substantially trailed their state's proficiency and graduation rates—often by 10 points or more. That's not to say that the urban districts didn't make gains. The good news is many did improve and at a rate faster than their states' 60 percent of the time—proof that the billionaires made some solid bets. But those spikes up weren't enough to erase the deep gulf between poor, inner-city schools, where the big givers focused, and their suburban and rural counterparts. "A lot of things we do don't work out," admitted Broad, a product of Detroit public schools and Michigan State who made a fortune in home building and financial services: "But we can take the criticism. " The confidence that marked Gates's landmark speech to the governors' association in 2005 has given way to humility. The billionaires have not retreated. But they have retooled, and learned a valuable lesson about their limitations. "It's so hard in this country to spread good practice. When we started funding, we hoped it would spread more readily," acknowledges Vicki Phillips, the director of K-12 education at the Bill ＆ Melinda Gates Foundation. "What we learned is that the only things that spread well in school are kids' viruses. " The business titans entered the education arena convinced that America's schools would benefit greatly from the tools of the boardroom. They sought to boost incentives for improving performance, deploy new technologies, and back innovators willing to shatter old orthodoxies. They pressed to close schools that were failing, and sought to launch new, smaller ones. They sent principals to boot camp. Battling the long-term worry that the best and brightest passed up the classroom for more lucrative professions, they opened their checkbooks to boost teacher pay. It was an impressive amount of industry. And in some places, it has worked out—but with unanticipated complications.

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