Early Childhood Longitudinal Study [United States]: Kindergarten Class of 1998-1999, Kindergarten-Eighth Grade Full Sample

The Early Childhood Longitudinal Study Kindergarten Class of 1998-1999, Kindergarten-Eighth Grade Full Sample includes the kindergarten, first, third, fifth, and eighth grade data collections for the Early Childhood Longitudinal Study, Kindergarten Class of 1998-1999 (ECLS-K). Unlike the public-use longitudinal files released in previous rounds, this file contains all data for all ECLS-K sample cases that have been publicly released in any of the rounds. Thus, it can be used for within-year (cross-sectional) analyses of any round of data collection and cross-year (longitudinal) analyses of combinations of rounds. It focuses on children's early school experiences beginning with kindergarten through eighth grade. It is a nationally representative sample that collects information from children, their families, their teachers, and their schools. ECLS-K provides data about the effects of a wide range of family, school, community, and individual variables on children's cognitive, social, emotional, and physical development, their early learning and early performance in school, as well as their home environment, home educational practices, school environment, classroom environment, classroom curriculum, and teacher qualifications. The list below summarizes each wave of this study. 1998-1999 (the Kindergarten year-Rounds 1 and 2): The ECLS-K child assessments, parent interviews, and teacher questionnaires were conducted in the fall. Children, parents, and teachers participated again in the spring, along with school administrators. 1999-2000 (the First grade year-Rounds 3 and 4): The ECLS-K conducted child assessments and parent interviews for a 30 percent sub-sample in the fall. The full sample of children, parents, teachers, and school administrators participated in the spring. 2002 (the Third grade year-Round 5): The ECLS-K conducted child assessments and parent interviews in the spring. Teachers and school administrators completed questionnaires. 2004 (the Fifth grade year-Round 6): The ECLS-K conducted child assessments and parent interviews in the spring. Teachers and school administrators completed questionnaires. 2007 (the Eighth grade year-Round 7): The ECLS-K followed the children into middle school. Information was collected from the children, their parents, teachers, and school administrators. For more detailed information about this data collection, please refer to the user guide.

1998-1999届幼儿园队列早期儿童纵向研究（Early Childhood Longitudinal Study Kindergarten Class of 1998-1999，以下简称ECLS-K）的幼儿园至八年级全样本数据集，涵盖了该研究在幼儿园、一年级、三年级、五年级与八年级阶段开展的全部数据采集内容。
与此前各轮次发布的公开使用纵向文件不同，本数据集囊括了ECLS-K所有轮次中已公开发布的全部样本案例的完整数据。
因此，本数据集可用于针对单一轮次数据采集的年度内（横断面）分析，以及针对多轮次组合的跨年度（纵向）分析。

本数据集聚焦于儿童从幼儿园至八年级的早期校园学习经历，为全国代表性样本，采集来自儿童本人、其家庭、教师以及学校的多维度信息。
ECLS-K提供了多维度变量的相关数据，涵盖家庭、学校、社区与个体层面的各类因素对儿童认知、社交、情绪与躯体发育的影响，儿童早期学习表现与在校学业表现，以及儿童家庭环境、家庭教育实践、学校环境、课堂环境、课堂课程设置与教师资质等内容。
下文汇总了本研究各轮次的开展情况：
1998-1999年（幼儿园阶段，第1、2轮）：秋季开展了ECLS-K儿童测评、家长访谈与教师问卷调研；春季则再次面向儿童、家长与教师开展相关工作，同时新增学校行政人员参与调研。
1999-2000年（一年级阶段，第3、4轮）：秋季仅针对30%的子样本开展儿童测评与家长访谈；春季则面向全部样本的儿童、家长、教师与学校行政人员开展调研。
2002年（三年级阶段，第5轮）：春季开展儿童测评与家长访谈，同时由教师与学校行政人员完成问卷填写。
2004年（五年级阶段，第6轮）：春季开展儿童测评与家长访谈，同时由教师与学校行政人员完成问卷填写。
2007年（八年级阶段，第7轮）：ECLS-K对升入中学的原样本儿童开展追踪调研，采集来自儿童本人、家长、教师与学校行政人员的相关信息。
如需了解本次数据采集的更多详细信息，请参阅用户指南。