Adequate Yearly Progress,Small Schools,and Students with Disabilities: The Importance of Confidence Intervals when Making Judgments about AYP

Abstract

Indicators of school-level achievement, such as the percentage of students who are proficient in a particular content area, are subject to random year-to-year variation in much the same way that the results of an opinion poll will vary from one random sample to another. This random variation, which is more pronounced for a small school, should be taken into account by education officials when evaluating school progress in a policy climate of high stakes. To do otherwise is to risk the false identification of a failing school, whether for all students combined or for the subgroup of students with disabilities. In this article, I describe the application of confidence intervals to the evaluation of “adequate yearly progress” for No Child Left Behind (NCLB). Throughout, I demonstrate the particular relevance of confidence intervals for small schools in general and, more specifically, for the (smaller still) subgroup of students with disabilities.