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Early Childhood Longitudinal Study, Kindergarten Class of 1998–99 (ECLS-K)

1. Overview

Early Childhood Longitudinal Study, Kindergarten Class of 1998–99 (ECLS-K)
ECLS-K collects data from:
  • Children
  • Parents/guardians
  • Teachers
  • School administrators

The Early Childhood Longitudinal Study (ECLS) program is one of the active longitudinal surveys sponsored by NCES. The ECLS program includes three cohorts: a birth cohort and two kindergarten cohorts (the kindergarten class of 1998–99 and the kindergarten class of 2010–11). The birth cohort study (ECLS–B) followed a sample of children born in 2001 from birth through kindergarten; the first kindergarten study (ECLS–K) followed a sample of children who were in kindergarten in the 1998–99 school year through the eighth grade; and the second kindergarten study (ECLS–K:2011) is following a sample of kindergartners in the 2010–11 school year through the fifth grade. The ECLS provides comprehensive and reliable datasets with information about the ways in which children are prepared for school and how children develop within their family, early childhood, and school environments.


The ECLS provides national data on (1) children’s status at birth and at various points thereafter; (2) children’s transitions to nonparental care, early education programs, and school; and (3) children’s experiences and growth through the eighth grade. These data enable researchers to test hypotheses about the associations and interactions of a wide range of family, school, community, and child characteristics with children’s development, early learning, and performance in school.


The ECLS has three cohort studies–two kindergarten cohort studies (ECLS–K and ECLS–K:2011) and a birth cohort study (ECLS–B)–and each of these has its own components. This chapter describes the first kindergarten cohort study, ECLS–K. For details on the 2011 kindergarten cohort study, see the handbook chapter for ECLS–K:2011. Details on the birth cohort study can be found in the ECLS–B handbook chapter.

The Early Childhood Longitudinal Study, Kindergarten Class of 1998–99. The ECLS–K collected data from children, their families, classroom teachers, special education teachers, school administrators, and student records. The various components are described below.

Direct child assessments. The direct child assessments covered several cognitive domains (reading and mathematics in kindergarten through eighth grade; general knowledge, consisting of science and social studies questions, in kindergarten and first grade; and science in third, fifth, and eighth grades); a psychomotor assessment (fall kindergarten only), including fine and gross motor skills; and height and weight measurements. The assessment for each cognitive domain included a routing test (to determine a child’s approximate skill level) and second-stage tests that were tailored to different skill levels. In kindergarten and first grade, a English language proficiency screener, the Oral Language Development Scale (OLDS), was administered to children if school records indicated that the child’s home language was not English. The child had to demonstrate a certain level of English proficiency on the OLDS to be administered the ECLS-K cognitive assessment in English. If a child spoke Spanish at home and did not have the English skills required for the ECLS-K battery, the child was administered a Spanish version of the OLDS, and the mathematics and psychomotor assessments were administered in Spanish. Beginning with the third-grade data collection, children reported on their own perceptions of their abilities and achievement, as well as their interest in and enjoyment of reading, math, and other school subjects. The student questionnaire covered many topics about the child’s school experiences, school-sponsored and out-of-school activities, self-perceptions of social and academic competence and interests, weight and exercise, and diet.

Parent interviews. Parents/guardians were asked to provide key information about their children and their families, such as the demographics of household members (e.g., age, relation to child, race/ethnicity), family structure (household members and composition), parent/guardian involvement at the school and with children’s schoolwork, home educational activities, children’s child care experiences, child health, parental/guardian education and employment status, and their children’s social skills and behaviors.

Classroom teacher questionnaires.. In the kindergarten collections, all kindergarten teachers with ECLS-K sampled children were asked to provide information on their educational backgrounds, teaching practices, teaching experiences, and the classroom settings in which they taught. They also were asked to complete a child-specific questionnaire that collected information on each sample child’s social skills and approaches to learning, academic skills, and education placements. This procedure continued in later rounds of the study. However, modifications were made beginning with the spring fifth-grade data collection, where the teachers who were most knowledgeable about the child’s performance in each of three core academic subjects (i.e., reading/language arts, mathematics, and science) provided the data pertinent to each child’s classroom environment and instruction for the academic subject about which they were most knowledgeable. Teachers also provided information about their professional background.

Special education teacher questionnaires. In each spring data collection, the primary special education teachers of and special education staff (e.g., speech pathologists, reading instructors, audiologists) who worked with sample children receiving special education services in school were asked to complete questionnaires about the children’s experiences in special education, as well as their own professional background. Items in the special education teacher questionnaires addressed topics such as the child’s disability, Individualized Education Program (IEP) goals, the amount and type of services sampled children received, and communication with parents and general education teachers about the child’s special education program and progress.

School administrator questionnaire. School administrators were asked about school characteristics (e.g., school type, enrollment, and student body composition), school facilities and resources, community characteristics and school safety, school policies and practices, school-family-community connections, school programs for particular populations (e.g., English language learners), staffing and teacher characteristics, school governance and climate, and their own characteristics.

Student records abstract. In each round of data collection except eighth grade, school staff members were asked to complete a student records abstract form for each sampled child after the school year ended. These forms were used to obtain information about the child’s attendance record, the presence of an IEP, the type of language or English proficiency screening that the school used, and (in the kindergarten year collection) whether the child participated in Head Start prior to kindergarten. A copy of each child’s report card was also requested.

School facilities checklist. In each round of data collection except eighth grade, field staff members completed a checklist providing information on school facilities. This checklist was used to collect information about the (1) availability and condition of the selected school’s facilities, such as classrooms, gymnasiums, and toilets; (2) presence and adequacy of security measures; (3) presence of environmental factors that may affect the learning environment; and (4) overall learning climate of the school. An additional set of questions on portable classrooms was added to the spring first-grade checklist.


The ECLS–K collected data in the fall and spring of kindergarten (1998–99), the fall of first grade (1999) (data were collected from a 30 percent subsample in this round), and in the springs of first grade (2000), third grade (2002), fifth grade (2004), and eighth grade (2007).