The Tennessee legislature sponsored a study on the effects of class size (Project STAR). The design and measurement techniques of this study are discussed. The establishment of the basic elements of the design is examined, followed by the recruitment of schools and school systems to participate in the study. The process of setting up smaller classes involved student achievement measures, teacher training, and selection of class type in order to provide objective cumulative effects. Appended are three references and a table of the basic design of Project STAR. (SI)