Introduction

The 2003 conference of the Brown Center on Education Policy of the Brookings Institution addressed the question of why the United States does not have the teachers it needs. While the media typically focus on a looming teacher shortage, the discussants went beyond the issue of quantity to ponder why it is that American schools always seem to be scrambling to find enough well-prepared and effective teachers. What can be done about a perennial teacher shortage for certain fields, especially mathematics and the sciences? Why are so many teachers assigned to teach subjects in which they have neither a major nor a minor? Is it more important for a future teacher to gain pedagogical knowledge or content knowledge? Why do so many urban schools have disproportionate numbers of teachers who are uncertified and inexperienced? Why are so many poor and minority children assigned to classes taught by rookie teachers? What can states and districts do to change the situation? These and many other issues related to teacher education, teacher preparation, teacher assignment, and teacher compensation were thoroughly debated by participants from a wide variety of disciplines and perspectives.

The papers and discussions in this volume examine the controversies that have been raging in policy circles for many years. As one would expect, no firm conclusions were reached by the end of the conference. Where so much dissension exists, the only meeting that might produce firm conclusions would be one in which the participants represent only a narrow range of the political spectrum. That was not the case. While the participants did not issue any ringing policy manifestos, their clear and cool analysis moves the issues closer to the formulation of good policies and worthy experiments by shedding light on important problems.

One of the distinguishing features of the annual Brown Center meetings, as compared with the usual conference on education, is the heavy representation of economists. This is intentional and reflects the Brookings Institution's long-standing commitment to a hard-headed, unsentimental economic analysis of policy issues. This strong element of economic analysis, I believe, has given the Brookings education conference a distinctive voice in the field of education, separating it from the run-of-the-mill forums that all too often seem to be afflicted with self-pleading and defensiveness (hardly surprising when many teacher educators are education researchers or work in the same institutions).

In their essay, Eric A. Hanushek and Steven G. Rivkin ask how the supply of high-quality teachers can be improved. Hanushek and Rivkin together have been responsible for much of the current research into the economic analysis of teacher quality. They review the state of research as it pertains to the relative value of teacher education, teacher experience, teacher testing, and teacher certification. Given the inadequacy of data now available, they conclude that value-added assessment of student achievement is likely the best measure of teacher quality. Using such data, they find that some teachers are able to bring about dramatic gains in achievement for their students. "A string of good teachers," they suggest, "can overcome the deficits of home environment ... and can push students with good preparation even further." But how does a state or district get good teachers? Most attempt to do so by tightening entry into teaching, but Hanushek and Rivkin argue that this is not the best way to identify good teachers. Nor would it be useful to raise all salaries, because both good and not-so-good teachers would benefit equally from such a move. They recommend that the best way to improve student performance is to focus relentlessly on student performance. The best quality teachers, they find, are those who succeed in improving student performance. The discussants, Richard Rothstein and Michael Podgursky, differ diametrically in their assessment of Hanushek and Rivkin's paper.

Richard M. Ingersoll reviews the causes of out-of-field teaching, a remarkably widespread phenomenon in American schools. Ingersoll, a leading researcher of this issue, has carried out numerous analyses for the U.S. Department of...