between 1970 and 1990, the number of people in the United States liv ing in high-poverty census tracts (with poverty rates of 40 percent or more) nearly doubled, from 4.1 to 8.0 million. Children who live in poor urban neighborhoods are disproportionately likely to be members of racial and eth nic minority groups and are also at greater risk for school failure. For example, only 11 percent of fourth graders attending high-poverty schools in Wash ington, DC, scored at or above basic level on the government's National Assessment of Educational Progress (NAEP) math test, far lower than the national average of 62 percent. Dropout rates in Washington remain on the order of 30 to 40 percent, many times higher than the national average. 1 Why do high-poverty urban areas have such problems with schooling out comes? Sociologists, psychologists, and a growing number of economists believe that the prevalence within a neighborhood of social problems such as poverty and joblessness affect the life chances of area residents. If so, policies