Inequality begets inequality: Income inequality and socioeconomic achievement gradients across the United States.

Social scientists have found income inequality is associated with an array of health and social problems, however the implications of income inequality for education are the subject of debate. Across 100 different areas (individual counties or collections of small counties) of the United States, we investigated how income inequality was associated with 1) average mathematics and reading achievement and 2) socioeconomic gradients in mathematics and reading achievement. Using data from the Kindergarten to Fifth Grade waves of the Early Childhood Longitudinal Study, Kindergarten Class of 2011 (ECLS-K 2011), we found areas of the United States with higher income inequality had lower average achievement in mathematics and a larger socioeconomic achievement gradient in reading. In further analyses, we investigated what characteristics of school and home environments mediated the relationship between income inequality and academic achievement. We found the association between income inequality and academic achievement was partly explained by the clustering of disadvantaged students in high poverty schools/districts and more intensive parenting practices among high SES parents (structured activity participation, educational expectations).