In this paper we combine National Assessment of Educational Progress and state accountability test data to examine variation among states in achievement gap levels and trends. Although national trends in gaps have been well studied, little research has examined variation in gaps across states or the extent to which differences in state demographics or policies account for these differences. We find that white-black and white-Hispanic achievement gaps are large and have been closing very slowly over the last two decades, but the sizes and rates of change of these gaps vary considerably across states. Much of the variation in gap levels, but none of the variation in gap trends, can be explained by differences across states in the socioeconomic status of minority children and school racial segregation.
