How Much and Why Does Class Size Matter?

描述（由申请人提供）：小班制对儿童学习的影响近年来受到越来越多的关注，因为实验研究（田纳西州STAR实验）的证据表明，小班制对小学生有显著的好处。尽管实验研究具有吸引力，但它们的范围仍然有限，因为它们的通用性，能够检查更广泛的结果，并探索班级规模可能影响儿童结果的机制。在本研究中，我们建议研究班级规模与儿童学习行为、教学实践、家长参与以及儿童认知和社会行为结果之间的关系。我们将使用来自幼儿纵向研究-幼儿园班级（ECLS-K）的面板数据，这是一个具有全国代表性的美国幼儿园样本，收集了多个时间点（幼儿园，一年级和三年级）儿童学习行为和学校成果，家长参与，教学实践和班级规模的详细信息。我们将把重点放在班级规模和教师与儿童的比例上，因为小学教师经常在课堂上使用助手来协助他们，这可能会影响孩子在课堂上得到的个人关注的数量。我们将估计儿童固定效应模型，该模型将利用同一儿童班级规模随时间的变化来确定班级规模效应。这种方法将消除与班级规模和感兴趣的结果相关的时间不变的个人和家庭不可观察性产生的任何偏差。这项研究的结果将是重要的，因为它们将有助于理解小班或大班可能影响儿童学习的机制，并将指导这一领域的政策制定。

DESCRIPTION (provided by applicant): The impact of small class size on children's learning has received increased attention in recent years as evidence from experimental studies (Tennessee STAR experiment) has shown significant benefits of smaller class size for elementary school children. Despite the appeal of experimental studies, their scope remains limited in terms of their generalizeability, ability to examine a wider range of outcomes and explore mechanisms through which class size may affect child outcomes. In this study, we propose to examine how class size is related to children's learning behavior, teaching practices, parental involvement and children's cognitive and social-behavioral outcomes. We will use panel data from the Early Childhood Longitudinal Study-Kindergarten Class (ECLS-K), a nationally representative sample of kindergartners in the U.S., which collected detailed information on children's learning behavior and school outcomes, parental involvement, teaching practices and class size at multiple time points (kindergarten, first grade, and third grade). We will focus on both class size and staff-to-child ratio because teachers in elementary school often use aides in class to assist them, which is likely to impact the amount of individual attention that children receive in class. We will estimate child fixed-effect models that will identify class-size effects using over time variation in class size for the same child. This approach will eliminate any bias generated from time invariant individual and family unobservables that are related to class size and the outcomes of interest. The findings of this study will be important because they will help to understand the mechanisms through which smaller or larger class sizes may affect children's learning and will guide policy making in this area.