Date of Conferral



Doctor of Education (Ed.D.)




David A. Hernandez


The school board of a school district in South Carolina has proposed to increase class size in all schools due to mandatory budgetary reductions. However, at the secondary school level, the literature on the effect of larger class size on student achievement is conflicting. The theoretical framework by Lazear suggested that the minimization of negative externalities (i.e., problematic behavioral and academic characteristics of students) achieved through the mechanism of smaller class size impacts student learning. Reducing the number of students in a classroom alters the entire classroom environment, creating a more positive learning environment in which students are able to forge better relationships with classmates and teachers. The research question for this study examined whether class size in secondary school predicted student achievement as measured by teacher-issued end-of-course numerical student grades (TIECNSG). The study used a correlational design with a sample of 17,582 TIECNSG from 5 secondary schools in the district. The effect of smaller class sizes on TIECNSG was determined through the use of a linear regression model. For 9 course offerings, an increase in class size resulted in a decrease in TIECNSG, whereas for 8 course offerings, an increase in class size resulted in an increase in TIECNSG. The results of this study, therefore, were inconclusive, suggesting that other unaccounted confounding variables may have affected student achievement. This study can be used to promote positive social change by creating a dialogue between parents and school administrators who often have opposing points of view in terms of the effects of class size. In addition, it is recommended that a district's school board should authorize additional studies prior to taking any course of action that would affect class size at the secondary school level.