I began exploring the relationship between schools and inequality after reading the 1992 article entitled “Summer Setback” by Doris Entwisle and Karl Alexander. The authors showed that gaps in math skills between advantaged and disadvantaged children in Baltimore grew faster when school was out in summer than when school was in during the rest of the year. The implication was shocking: schools were reducing the gaps we would likely observe if children were not there. Schools were compensatory.At first, I thought there was something odd with the Baltimore study. But when my colleagues and I replicated this pattern with the nationally representative Early Childhood Longitudinal Study—Kindergarten Cohort of 1998 (ECLS-K:1998), I was forced to rethink my earlier assumption that schools were generating significant inequality in math and reading skills.The ECLS-K:1998 data were collected by the Department of Education and are among the highest quality education data available. The study consists of over 20,000 children attending kindergarten in roughly 1,200 schools in the fall of 1998-99. One unusual feature of the data is that children were tested in both fall and spring of kindergarten and first grade, allowing researchers to observe how fast children learned both when school was in and when it was out (summer).My team of researchers at Ohio State analyze a restricted-use version of the ECLS-K:1998 data, which allows us to link children’s scores on reading and math tests to their personal information, like their socioeconomic status. To protect the anonymity of the respondents we are required to analyze the data on a standalone computer, lacking any connection to the internet. On random occasions, officials from the Department of Education arrive at my office and inspect our data protection protocols to ensure that we are handling the data appropriately. This creates extra work for us, but it is important so that parents can feel comfortable that their answers to the questionnaires will be kept confidential.