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Teacher shortages have posed a serious problem in K–12 education for the past century. Beginning in the late 1990s, Professor Ingersoll embarked on research that revealed that the longstanding conventional wisdom on teacher shortages has produced a wrong diagnosis and a wrong set of prescriptions. He found that teacher staffing problems do not stem primarily from an insufficient supply of qualified teachers caused by teacher retirements and rising student enrollments, as is widely believed. Rather, school staffing difficulties arise primarily from a “revolving door” syndrome, in which large numbers of qualified teachers depart their jobs for reasons other than retirement—reasons often directly connected to teachers’ working conditions and the way schools are organized and managed. His findings demonstrated that a focus on teacher recruitment—the dominant practice for decades—would not solve the staffing crisis on its own. The problem called for a robust effort to improve teacher retention.

Professor Ingersoll summarized this initial research in a 2001 article in the American Educational Research Journal. The article has been cited more than 5,000 times and downloaded more than 28,000 times from the University of Pennsylvania’s Scholarly Commons website. In subsequent research, Professor Ingersoll and colleagues Henry May and David Perda focused particularly on the math and science teacher shortage and how various factors, such as school conditions and preservice teacher preparation, influence teacher turnover. Collectively, Professor Ingersoll’s publications on shortages and turnover have been cited almost 15,600 times and downloaded 71,000 times.

Major media outlets such as Education Week, The Atlantic, PBS, and Science magazine have reported on this research, and Professor Ingersoll has presented his findings to a wide variety of audiences, including researchers, educators, school leaders, policymakers, and the public.

These research findings have also figured prominently in high-profile education reports from the National Commission on Teaching and America’s Future, the National Retired Teachers Association, the National Education Association, the National Association of State Boards of Education, the Southeast Center for Teaching Quality, the Southern Regional Educational Board, the National Science Teachers Association, the California Math Project, and the Center for American Progress.

This research holds interest for legislators and policymakers. The National Commission on Mathematics and Science Teaching for the 21st Century commissioned Professor Ingersoll to write a paper summarizing his research on turnover among math and science teachers. He presented this research to the Science and the Congress Briefing, co-chaired by Representatives Vernon Ehlers and Rush Holt and Senators James Jeffords and Joseph Lieberman. He also reported on this research as part of a series of seminars for new members of Congress, sponsored by the U.S. House of Representatives. President Obama’s Council of Advisors on Science and Technology made extensive use of his work. Professor Ingersoll has testified and presented this research before the Education Committee of the Council of the City of New York, the Campaign for Human Capital of the School District of the City of Philadelphia, and official education commissions and forums in numerous states, including Ohio, Arizona, South Dakota, Pennsylvania, Delaware, Indiana, Georgia, Virginia, Texas, Florida, South Carolina, and Montana.

Updated: Feb 16

Problems with the quality, qualifications, and preparation of elementary and secondary school teachers have long persisted in America’s schools. In the early 1990s, Professor Ingersoll began a research study that uncovered a major source of underqualified teachers. He learned that out-of-field teaching—the practice of assigning teachers to teach subjects that do not match their preparation and training—was a primary contributor to this problem. Working with analysts Sharon Bobbitt and Marilyn Seastrom from the National Center for Education Statistics, he developed accurate measures of out-of-field teaching—something never done before. His research showed that this practice, while largely unknown to the public, is widespread in U.S. schools. Professor Ingersoll published a series of reports, articles, and essays documenting that out-of-field teaching, contrary to conventional wisdom, does not result from inadequate teacher preparation or teacher shortages. Rather, this practice is rooted in the manner in which schools and teachers are managed and in the organizational need to staff classrooms as efficiently and inexpensively as possible while serving an increasingly large and diverse student population. Professor Ingersoll has also studied other aspects of teacher preparation and quality, including the effects of teachers’ preservice preparation on their retention and the myths surrounding the problem of low-quality teachers and teaching. These publications have been cited 3,300 times and downloaded more than 28,000 times from the University of Pennsylvania’s Scholarly Commons website.

His research on underqualified teachers has drawn national recognition and media attention. President Clinton quoted Professor Ingersoll’s findings in several speeches (for example, his speech to the NAACP in July 1997 announcing his teacher recruitment and training initiatives). In February 1998, Professor Ingersoll testified on this research at the Congressional Hearings on Teacher Preparation Initiatives held by the U.S. House of Representatives Committee on Education and the Workforce. His research influenced the development of the No Child Left Behind Act, especially the Highly Qualified Teacher regulations arising from that legislation. The results of this research have been featured in reports from numerous groups, including the Education Trust, the National Governors' Association, the Committee for Economic Development, the Brookings Institute, the National Association of State Boards of Education, the Milken Family Foundation, the Century Foundation, the Aspen Institute, and the Organization for Economic Co-operation and Development. From 2005 to 2007, Professor Ingersoll served on a National Academy of Sciences/National Research Council Committee that examined National Board Certification for teachers.

Updated: Feb 16

For decades, education commentators and reformers have called attention to the challenges encountered by new teachers. Traditionally, elementary and secondary school teachers have been left to succeed or fail on their own in the classroom, a situation that teachers have often described as a “lost at sea” or “sink or swim” experience. As a result, school districts throughout the country have in recent decades instituted support programs for new teachers, a practice known as induction.

In 2002 Professor Ingersoll began research to examine the problems encountered by new teachers, including rates of attrition and the reasons for it, how many new teachers receive support, what kinds of induction they receive, and finally, whether these supports help retain teachers, improve their instruction, and boost their students’ achievement.

He summarized his initial research in two publications (co-authored with Thomas Smith), including a 2004 article in the American Educational Research Journal. These two publications have been cited almost 4,000 times and downloaded more than 31,000 times from the University of Pennsylvania’s Scholarly Commons website.

A 2011 review article (co-authored with Michael Strong) in the Review of Educational Research provided policymakers, educators, and researchers with a reliable assessment of what is known, and not known, about the effectiveness of beginning-teacher induction and mentoring programs. This article has been cited almost 2,000 times and downloaded more than 52,000 times from the University of Pennsylvania’s Scholarly Commons website.

The findings from this research have been featured in reports from organizations such as the Alliance for Excellence in Education, and the work has garnered widespread interest from school leaders and local, state, and federal legislative and policymaking groups.

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