Kids who attend New York City's Success Academy charter schools do remarkably well. "We are No. 1 in student achievement in the state," says founder Eva Moskowitz, "outperforming all the wealthy suburbs." They do. Although they teach mostly poor kids, 95 percent pass the state math test, and 84 percent pass the English test. Pass rates at government run schools are 38 and 41 percent. How does Success Academy do it? For one thing, she keeps kids in class longer. Middle schoolers stay until 4:30 p.m. Is that too much stress for kids, I ask? "China and India are not...