Educational Leadership

and 1970s and the sharp increase in economic inequality in education outcomes in more recent decades.

Indeed, Figure 1 encapsulates two important trends in U.S. history over the last 50 years. In the 1950s and 1960s, racial inequality was high in virtually every domain of life— education, health, earnings, residential segregation—whereas economic inequality was lower than it had ever been in the last century (Piketty & Saez, 2003). By the early part of the 21st century, racial inequality was much lower (although far from eliminated) in terms of wages, health disparities, and residential segregation. Meanwhile, economic inequality reached historic highs (Saez, 2012). Although both remain high, economic inequality now exceeds racial inequality in education outcomes.

FIGURE 1. Income Achievement Gap and Black-White Achievement Gap in Reading for 1943–2001 Birth Cohorts

1. 50

Average Difference in Standardized Test Scores

(90/10 Income Gap or Black-White Gap) In standard deviation units

1. 25

1.00

. 75

. 50

. 25

Income Gap Black-White Gap

1940 .00

1950

1960 1970 1980 Cohort Birth Year

1990 2000

Finding 2: Income gaps in other measures of education success have grown as well.

Academic achievement, as measured by standardized test scores, is not the only education outcome for which disparities between high-income and low-income students have been growing. The college-completion rate among children from high-income families has grown sharply in the last few decades, whereas the completion rate for students from low-income families has barely moved (Bailey & Dynarski, 2011). Moreover, high-income students make up an increasing share of the enrollment at the most selective colleges and universities (Reardon, Baker, & Klasik, 2012)—even when compared with low-income students with similar test scores and academic records (Bailey & Dynarski, 2011; Belley & Lochner, 2007; Karen, 2002).

A related trend during the last 20 years is the growing social-class gap in other important measures of adolescents’ “soft skills” and behaviors related to civic engagement, such as participating in extracurricular

Source: Adapted from “The Widening Socioeconomic Status Achievement Gap: New Evidence and Possible Explanations” (p. 98) by S. F. Reardon, in R. J. Murnane & G. J. Duncan (Eds.), Whither Opportunity? Rising Inequality, Schools, and Children’s Life Chances, 2011, New York: Russell Sage Foundation.

activities, sports, and academic clubs; volunteering and participating in community life; and self-reports of social trust (Putnam, Frederick, & Snellman, 2012).

Finding 3: The income achievement gap is already large when children enter kindergarten, and it does not grow significantly as they progress through school.

One possible explanation for the widening income achievement gap is that K–12 schools have grown more unequal in quality over the last few decades. If this were true, then the gap should grow larger the longer students are in school. But when I examined the data, I found little evidence that this occurs.

In one study, the Early Childhood Longitudinal Study-Kindergarten Cohort (ECLS-K), roughly 25,000

students were tested in math and literacy skills in kindergarten in 1998 and then were reassessed as many as six more times between 1998 and 2007, when the students were in 8th grade (Tourangeau, Nord, Lê, Pollack, & Atkins-Burnett, 2006). I used this study’s data to examine how the income achievement gap changed as this cohort of students progressed through elementary and middle school. As Figure 2 (p. 15) shows, the gap in reading grew very little during this period—it was 1. 15 standard deviations when the children entered kindergarten and 1. 25 standard deviations in 8th grade. Other longitudinal studies that assessed students multiple times during middle and high school show the same pattern: The achievement gap changes little during the K–12 years.