Using data for North Carolina public school students in grades 3 to 8, we examine achievement gaps between white students and students from other racial and ethnic groups. We focus on cohorts of students who stay in the state's public schools for all six years. While the black-white gaps are sizable and robust, both Hispanic and Asian students tend to gain on whites as they progress in school. Beyond simple mean differences, we find that the racial gaps in math between low-performing students have tended to shrink as students progress through school, while those for high-performing students have generally widened.

This paper uses decennial Census data to examine the residential integration of the foreign born in the United States between 1910 and 2000. Immigrant segregation declined in the first part of the century, but has been rising over the past few decades. Recent immigrants tend to hail from countries with greater cultural distinctions from U.S. natives, whether economic, racial, or linguistic. These factors explain much of the increase in segregation after 1970. Evidence also points to changes in urban form, particularly native-driven suburbanization and the decline of public transit as a transportation mode, as an explanation for the new immigrant segregation.

This paper examines segregation in American cities from 1890 to 1990. We divide the century into three time periods. From 1890 to 1940, ghettos were born as blacks migrated to urban areas and cities developed vast expanses filled with nearly exclusively black housing. From 1940 to 1970, black migration continued and ghettos expanded. Since 1970, there has been a decline in segregation as blacks have moved to suburban areas and central cities have become less segregated. Across all of these time periods there is a strong positive relation between urban population or density and segregation. We then examine why segregation has varied so much over time. We find evidence that the mechanism sustaining segregation has changed. In the mid-20th century taken by whites to exclude blacks from their neighborhoods. By 1990, these legal barriers enforcing segregation had been replaced by decentralized racism, where whites pay more than blacks to live in predominantly white areas.