Appendix A.2. Early Childhood Longitudinal Study, Kindergarten Class of 2010–11

The Early Childhood Longitudinal Study, Kindergarten Class of 2010–11 (ECLS-K:2011) provides detailed information on the school achievement and experiences of students throughout their elementary school years. The students who participated in the ECLS-K:2011 were followed longitudinally from the kindergarten year (the 2010–11 school year) through the spring of 2016, when most of them were expected to be in 5th grade. This sample of students is designed to be nationally representative of all students who were enrolled in kindergarten or who were of kindergarten age and being educated in an ungraded classroom or school in the United States in the 2010–11 school year, including those in public and private schools, those who attended full-day and part-day programs, those who were in kindergarten for the first time, and those who were kindergarten repeaters. Students who attended early learning centers or institutions that offered education only through kindergarten are included in the study sample and represented in the cohort.

The ECLS-K:2011 places emphasis on measuring students' experiences within multiple contexts and development in multiple domains. The design of the study includes the collection of information from the students, their parents/guardians, their teachers, and their schools. Information was collected from their before- and after-school care providers in the kindergarten year.

A nationally representative sample of approximately 18,170 children from about 1,310 schools participated in the base-year administration of the ECLS-K:2011 in the 2010–11 school year. The sample included children from different racial/ethnic and socioeconomic backgrounds. Asian/Pacific Islander students were oversampled to ensure that the sample included enough students of this race/ethnicity to make accurate estimates for the group as a whole. Eight data collections have been conducted to date: fall and spring of the children's kindergarten year (the base year), fall 2011 and spring 2012 (the 1st-grade year), fall 2012 and spring 2013 (the 2nd-grade year), spring 2014 (the 3rd-grade year), and spring 2015 (the 4th-grade year). The final data collection was conducted in the spring of 2016. Although the study refers to later rounds of data collection by the grade the majority of children are expected to be in (that is, the modal grade for children who were in kindergarten in the 2010–11 school year), children are included in subsequent data collections regardless of their grade level.

A total of approximately 780 of the 1,310 originally sampled schools participated during the base year of the study. This translates to a weighted unit response rate (weighted by the base weight) of 63 percent for the base year. In the base year, the weighted child assessment unit response rate was 87 percent for the fall data collection and 85 percent for the spring collection, and the weighted parent unit response rate was 74 percent for the fall collection and 67 percent for the spring collection.

Fall and spring data collections were conducted in the 2011–12 school year, when the majority of the children were in the 1st grade. The fall collection was conducted within a 33 percent subsample of the full base-year sample, and the spring collection was conducted within the full base-year sample. The weighted child assessment unit response rate was 89 percent for the fall data collection and 88 percent for the spring collection, and the weighted parent unit response rate was 87 percent for the fall data collection and 76 percent for the spring data collection.

In the 2012–13 data collection (when the majority of the children were in the 2nd grade) the weighted child assessment unit response rate was 84.0 percent in the fall and 83.4 percent in the spring. In the 2014 spring data collection (when the majority of the children were in the 3rd grade), the weighted child assessment unit response rate was 79.9 percent.

Further information on ECLS-K:2011 may be obtained from

Gail Mulligan
Jill McCarroll
Longitudinal Surveys Branch
Sample Surveys Division
National Center for Education Statistics
550 12th Street SW
Washington, DC 20202
ecls@ed.gov
http://nces.ed.gov/ecls/kindergarten2011.asp