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What makes a great high school? Americans think a lot of things do, from outstanding academics or a supportive environment for students to a great football or basketball team. Still, pretty much everyone agrees teaching and learning are central to the mission. High schools are expected to prepare students for further education, work, or the military and eliminate the large gaps in achievement separating different ethnic and income groups of students. These are sensible goals. While there are many great high schools among the nearly 22,000 across the country, too many are still not getting the job done. Only about half of African-American and Hispanic students finish high school on time. Meanwhile, the National Assessment of Education Progress tests, often referred to as "the nation's report card," show significant achievement gaps separating white students from black and Hispanic high school students. These are not small differences but rather vast gaps that crush opportunity and tear at our nation's social contract. Leave aside the intrinsic value of being an educated citizen; there are practical effects as well. In 2005, the mean annual earnings were about $20,000 for a high school dropout but $54,000 for someone with a bachelor's degree. And those differences are growing wider, not lessening, as our economy becomes more knowledge and skills based. In 1975, a high school dropout earned about half as much as a college graduate, compared with about one third today. This is why U.S. News set some clear criteria for academic quality in its new ranking of American high schools. These criteria mean a lot of schools don't measure up—only 505 schools nationwide earned a silver or gold medal this year. The list illustrates at once the promise and the challenge for high schools today. Only about 1 in 8 of the schools on this list serves a student population that is more than 50 percent low income, and only about 1 in 5 has a majority of nonwhite students. Meanwhile, about 1 in 5 selects students based on academic merit, something that obviously boosts the chances of meeting the criteria. Because the U.S. News list uses more data to judge schools, it paints a clearer picture. Of course, no list is perfect. For instance, it is difficult to account for high school graduation rates because states calculate them in different ways. But this one better reflects what policymakers and parents want from high schools, as well as the challenge our nation faces to make our high schools as good as they need to be.