Teachers make a difference. The success of any plan for improving educational outcomes depends on the teachers who carry it out and thus on the abilities of those attracted to the field and their preparation. Yet there are many questions about how teachers are being prepared and how they ought to be prepared. As mandated by Congress, the U.S. Department of Education requested that the National Research Council conduct a study of teacher preparation with specific attention to reading, mathematics, and science. The Committee on the Study of Teacher Preparation Programs in the United States was charged to address four questions:
What are the characteristics of the candidates who enter teacher preparation programs?
What sorts of instruction and experiences do teacher candidates receive in preparation programs of various types?
To what extent are the required instruction and experiences consistent with converging scientific evidence?
What model for data collection would provide valid and reliable information about the content knowledge, pedagogical competence, and effectiveness of graduates from the various kinds of teacher preparation programs?
We examined many aspects of the complex and diverse network through which the majority of the nation’s teachers are prepared. It was exceptionally difficult to assemble a clear picture of teacher preparation because
there have been no systematic efforts to collect the necessary data; thus, we can provide only partial answers to the first three questions in our charge. However, we did find many sources for conclusions about the skills and knowledge most likely to be valuable to beginning teachers, as well as clear indications of the research that is most needed to build a base of knowledge to guide improvements to teacher education.
HOW TEACHERS ARE PREPARED AND CERTIFIED
The lack of data related to the first two questions in our charge, about the characteristics of teacher candidates and how they are prepared, is surprising—at the very least because of the huge scale of the enterprise. There are approximately 3.6 million public school elementary and secondary teachers in 90,000 public schools in the United States. More than 200,000 students complete a teacher preparation program each year. Little is known about these teacher candidates except that they are predominantly female and white.
Aspiring teachers in the United States are prepared in many different kinds of programs, which in turn reflect many different kinds of career pathways. Between 70 and 80 percent are enrolled in “traditional” programs housed in postsecondary institutions; the rest enter the profession through one of the approximately 130 “alternative” routes.
Yet however they are designated, teacher preparation programs are extremely diverse along almost any dimension of interest: the selectivity of programs, the quantity and content of what they require, and the duration and timing of coursework and fieldwork. Any pathway is likely to entail tradeoffs among selectivity, the intensity of the training, and the obstacles it presents to teacher candidates. More selective pathways, and those that require greater effort and time to complete, may have the disadvantage of yielding fewer teachers to fill vacancies, for example, but the teachers they do produce may be more highly qualified.
There is some research that suggests that there are differences in the characteristics of teacher candidates who are attracted to different pathways and types of programs. There is also some research comparing the outcomes for graduates of different kinds of programs. However, the distinctions among pathways and programs are not clear-cut and there is more variation within the “traditional” and “alternative” categories than there is between these categories. We found no evidence that any one pathway into teaching is the best way to attract and prepare desirable candidates and guide them into the teaching force. This finding does not mean that the characteristics of pathways do not matter; rather, it suggests that research on the sources of the variation in preparation, such as selectivity, timing, and specific components and characteristics, is needed.
The wide variety in teacher education programs led us to consider the current mechanisms for accountability and quality control in teacher education, which strongly affect the ways that teachers are prepared. These mechanisms are a patchwork of mandatory and voluntary processes, including state program approval, program accreditation, and teacher licensure and certification. These mechanisms are not effectively linked in a coherent, outcomes-driven accountability system, and they are not grounded in solid empirical research about which program elements or accountability mechanisms are most effective, partly because such research is not available. Thus, they neither achieve the goal of a true accountability system nor provide evidence about the value of different mechanisms for producing effective teachers. In view of this lack of information, the committee recommends that the U.S. Department of Education undertake an independent evaluation of teacher education approval and accreditation in the United States.
For the third question in our charge, about the extent to which current practices in the preparation of mathematics, reading, and science teachers are consistent with converging scientific evidence, we found a range of potential relevant material. This material included a relatively small body of evidence about the effects of particular kinds of instruction and an even smaller body of evidence about the effects of particular approaches to teacher preparation. Other available research included descriptive and qualitative studies about many aspects of teaching and learning in the three subjects and a substantial body of empirical work on learning and cognition. In addition, the relevant professional organizations have drawn on the available research and their own intellectual traditions and experience as educators to develop content and achievement standards for students and for teachers and, in some cases, for teacher education.
These sources together provide the basis for conclusions about:
what successful students know about the subject,
what instructional opportunities are necessary to support successful students,
what successful teachers know about the subject and how to teach it, and
what instructional opportunities are necessary to prepare successful teachers.
In analyzing the available evidence, we were mindful of the need to distinguish the basis for different sorts of claims and arguments, even as we
synthesized the most important points for policy makers and teacher educators and highlighted questions that have yet to be answered.
There has been an extraordinary amount of work, from a variety of fields, on questions about the factors that influence the effectiveness of teaching, but this work is only a starting point. There is little firm empirical evidence to support conclusions about the effectiveness of specific approaches to teacher preparation. However, we found no reason to question the recommendations professional societies have made about what is important for teachers to know. Moreover, those recommendations integrate well with the relatively small body of empirical work. The research base is strongest for reading and least strong for science, and our conclusions about preparation in the three fields reflect these differences.
In general, the evidence base supports conclusions about the characteristics it is valuable for teachers to have, but not conclusions about how teacher preparation programs can most effectively develop those characteristics. For all three fields, we conclude that both strong content knowledge (a body of conceptual and factual knowledge) and pedagogical content knowledge (understanding of how learners acquire knowledge in a given subject) are important.
For teachers of reading, it is important to (1) understand that students must master the foundational skills of reading (which include a firm grasp of phonics and comprehension strategies), and (2) possess a range of approaches for helping all students develop this mastery.
In mathematics, it is important for teachers to be able to foster students’ understanding of the core elements of mathematical proficiency (which include conceptual understanding, procedural fluency, and capacity for reasoning and problem solving). This capacity requires not only mathematical knowledge, but also understanding of how mathematics learning develops and of the variation in cognitive approaches to mathematical thinking.
In science, the key points are similar to those for mathematics teachers: a grounding in college-level study of the science disciplines suitable to the age groups and subjects they intend to teach; understanding of the objectives for students’ science learning; understanding of the way students develop science proficiency; and command of an array of instructional approaches designed to develop students’ learning of the content, intellectual conventions, and other attributes essential to science proficiency.
This was the picture we found of the evidence relevant to teacher preparation. There is very little systematic research regarding the specific ways teachers of reading, mathematics, and science are currently being prepared that we could use to make comparisons with that picture. The limited information we found does not support conclusions about the current nature and content of teacher preparation programs.
Ideally, teacher education programs would be evaluated on the basis of the demonstrated ability of their graduates to improve the educational outcomes of the students they teach. Unfortunately, the data needed for such evaluation do not exist, although there has been some promising work. More such research is needed, but identifying and measuring the relationship between teacher preparation and student outcomes poses methodological difficulties.
First, it is difficult to measure teacher effectiveness in valid and reliable ways. Assessments of K-12 student learning are the most readily available quantitative measures of educational outcomes. These types of measures serve important purposes, but they do not address the full range of outcomes of concern to policy makers. Indeed, much of the K-12 curriculum is not addressed by such tests. The assessment community has made important strides in developing richer measures of achievement but these are not yet at the stage where they could be easily used for systematic analysis of teacher effectiveness.
Second, establishing clear causal links between aspects of teacher preparation and outcomes for students is extremely difficult. The effects of teacher preparation are hard to disentangle from other factors, such as school, curriculum, community, and family influences. Efforts to establish causal links are also hobbled by the relative lack of data on the characteristics of teachers and their preparation; the dearth of robust measures of teachers’ knowledge and practice; and difficulties in linking student achievement to instruction or to what teachers know. And, there is considerable distance in time and place between teachers’ preparation and the effects their teaching may later have on student achievement.
These obstacles partly account for the paucity of strong empirical evidence regarding the effects of teacher preparation. Yet we believe that building knowledge about teacher preparation, as in any field of scholarly inquiry, requires ambitious and creative approaches to empirically examining causal relationships. It is very important to connect what occurs in preparation programs to characteristics of their graduates, to the ways those teacher-graduates interact with their students, and to learning outcomes for those students.
A MODEL FOR FUTURE RESEARCH
Because the information about teacher preparation and its effectiveness is so limited, high-stakes policy debates about the most effective ways to recruit, train, and retain a high-quality teacher workforce remain muddled. If the base of empirical knowledge about teacher preparation is thin, the way
forward is to build on what has been done by drawing on the professional consensus in each academic field for hypotheses about which features of teacher preparation are most promising and to subject those hypotheses to rigorous research. We were asked to develop an approach to future research that would provide a firmer foundation for policy and practice in the future. We organized our response around two overarching needs:
improved understanding of the relationships between characteristics of teacher preparation and student learning, and
a comprehensive, coherent system for collecting data about teacher preparation.
High-Priority Research Questions
The primary need is to build a body of evidence, developed from multiple perspectives and using an array of research designs, that establishes links between teacher preparation and learning—both teachers’ learning and K-12 students’ learning. Particularly valuable will be research that identifies and explains
the features that make programs attractive to academically accomplished teacher candidates,
the ways teachers’ knowledge affects outcomes for students, and
the characteristics of clinical experiences that affect outcomes for the students teacher candidates will later teach.
A comprehensive data collection system would provide not only baseline information for identifying and monitoring trends in teacher preparation, but also the necessary infrastructure for research into complex questions about teacher preparation.
A comprehensive data system for teacher preparation would provide meaningful information about teacher candidates, preparation programs, practicing teachers, the schools where those teachers teach, and the students they teach: that is, it would incorporate indicators beyond standardized test scores, degree title, courses taken, or certification category. These data would be integrated so that information about teacher candidates and their preparation can be connected with their knowledge, teaching practices, career paths, school environments, and student outcomes. One key to integration will be consistent definitions of key indicators so that data from states can be compared and used for research.
As states pursue strategies for sharing data and making it more accessible
through web-based systems, possibilities for research in teacher preparation will expand. The federal government can play a critical role in coordinating states’ efforts and encouraging them to move in this direction.
The quality of the nation’s teachers has been the subject of sharp critiques, and so have many preparation programs. Yet, teacher preparation is often treated as an afterthought in discussions of improving the public education system. Federal and state policy makers need reliable, outcomes-based information to make sound decisions, and teacher educators need to know how best to contribute to the development of effective teachers. Clearer understanding of the content and character of effective teacher preparation is critical to improving it and to ensuring that the same critiques and questions are not being repeated 10 years from now.