Have Income-Based Achievement Gaps Widened or Narrowed?

Over the past 30 years, rising income inequality and income-based residential segregation have threatened to widen income-based achievement gaps. Yet, there are no national data which combine a consistent measure of parental income and achievement for individual students to measure those gaps over time. We take two alternative approaches to inferring income-based achievement gaps: First, we reconstruct the student-level relationship using school-level estimates of means and variances of achievement and income. Second, we combine estimates of mean income by race, mother’s education, urbanicity and state with mean achievement for the corresponding subgroups on a national assessment. Using both methods, we find that income-based achievement gaps in 4th and 8th grade narrowed between 1992 and 2015—while math scores rose at all income levels.