Jepsen, Christopher, and Steven Rivkin. 2009. “Class Size Reduction and Student Achievement: The Potential Tradeoff between Teacher Quality and Class Size.” Journal of Human Resources 44(1): 223–250.
This paper investigates the effects of California’s billion-dollar class-size-reduction program on student achievement. It uses year-to-year differences in class size generated by variation in enrollment and the state’s class-size-reduction program to identify both the direct effects of smaller classes and related changes in teacher quality. Although the results show that smaller classes raised mathematics and reading achievement, they also show that the increase in the share of teachers with neither prior experience nor full certification dampened the benefits of smaller classes, particularly in schools with high shares of economically disadvantaged, minority students.
Christopher Jepsen is an assistant professor of economics at the University of Kentucky. Steven Rivkin is a professor of economics at Amherst college, National Bureau of Economic Research, and University of Texas at Dallas respectively. The authors thank three anonymous referees, Mark Baldassare, Julian Betts, David Figlio, Gary Hart, Caroline Minter Hoxby, Robert McMillan, Kim Rueben, Jon Sonstelie, Geoffrey Woglom, and seminar participants at the Public Policy Institute of California, Stanford University, NBER, the Fall 2001 APPAM conference, and the 2003 SOLE meetings for their many helpful comments. They also thank Anne Danenberg for invaluable data support and Pedro Cerdan, Jackie Chou, and Shelley de Alth for excellent research assistance. Financial support for Rivkin was provided by Smith Richardson Foundation, Spencer Foundation, Mellon Foundation and Hewlett Foundation. The data used in this article can be obtained beginning July 2009 through June 2012 from Christopher Jepsen, Department of Economics, 335BA Gatton B&E Building, Lexington, KY 40506-0034 jepsen@uky.edu.