This brief leverages the first ever nationally representative data set with a direct assessment of elementary school-aged children's executive function skills to examine racial and socioeconomic gaps in performance. The analysis reveals large gaps in measures of working memory and cognitive flexibility, the two components of executive function included in the Early Childhood Longitudinal Study, Kindergarten Class of 2010-11 (ECLS-K:2011), based on racial group membership and socioeconomic status. Children's initial gaps on entry into kindergarten in executive function measures are generally lower than gaps in measures of math and reading achievement. Furthermore, as children progress to the end of second grade, gaps in executive function skills commonly narrow for Black and Hispanic students as well as each socioeconomic status quintile. Implications and directions for future research are discussed.