How and Why Do Teacher Credentials Matter for Student Achievement? C HARLES T. C LOTFELTER H ELEN F. L ADD J A C OB L. V IGDOR w o r k i n g p a p e r 2 • m a r c h 2 0 0 7 How and why do teacher credentials matter for student achievement?* Charles T. Clotfelter Helen F. Ladd Jacob L. Vigdor Sanford Institute, Duke University Corresponding author: Helen F. Ladd.
[email protected]. Revised, January 2007 *This paper is a revised version of a paper initially prepared for a conference organized by the World Bank on “The Contribution of Economics to the Challenges Faced by Education,” Dijon, France, June 2006. An earlier version of this paper was presented in March 2006 at the annual meetings of the American Education Finance Association, Denver, Colorado. The authors are grateful to the Spencer Foundation and the National Center for the Analysis of Longitudinal Data in Education Research (CALDER) housed at the Urban Institute (U.S. Department of Education Grant Award No. R305A060018), for support for this project, to the North Carolina Education Research Data Center for the data, and to Aaron Hedlund for excellent research assistance. Other research assistants, including Trip Stallings and Roger Aliaga-Diaz, contributed to earlier stages of this research project. We are grateful to them all. CALDER working papers have not gone through final formal review and should be cited as working papers. They are intended to encourage discussion and suggestions for revision before final publication. Any opinions, findings, and conclusions expressed in these papers are those of the author(s) and do not necessarily reflect the views of the Urban Institute, the U.S.