This report is intended to provide a snapshot of the children in the ECLS-K:2011 cohort who were in kindergarten for the first time in the 2010-11 school year and in fourth grade 4 years later during the spring of 2015. About 88 percent of children enrolled in kindergarten in 2010-11 were in kindergarten for the first time that school year and were in fourth grade in the spring of 2015. The remaining 12 percent includes children who were repeating kindergarten in 2010-11 or who were not in fourth grade in the spring of 2015, including children who had been retained or advanced resulting in enrollment in a grade other than fourth, or who were in an ungraded classroom or setting in the spring of 2015. Information is presented on selected child and family characteristics, such as poverty status, parental education, family type, and primary home language (table 1), obtained when the children were in kindergarten. Information is also provided on the children's knowledge and skills in reading (table 2), math (table 3), and science (table 4) in the spring of fourth grade, both overall and by the selected kindergarten-year child and family characteristics.