1
Introduction

Teachers make a difference. Indeed, of all the factors that education leaders can control, the quality of teaching has perhaps the greatest potential effect (see, e.g., Wenglinsky, 2002; Rockoff, 2004; Rivkin, Hanushek, and Kain, 2005; Clotfelter, Ladd, and Vigdor, 2007). Policy has begun to reflect this perspective, most prominently in the provision of the No Child Left Behind Act of 2001 (NCLB) that requires that all public school teachers in core academic areas be highly qualified by 2012. Teacher qualifications and preparation are likely to remain in focus even as the policy environment for education reform shifts. Yet many questions about what it takes to produce highly qualified teachers, and about how teachers are currently prepared, do not have clear answers. Who enters teaching and what educational options are available to aspiring teachers? What should teachers be required to study? Should all teachers be required to complete a program of professional education, culminating in a university degree? Are U.S. teachers provided with real opportunities to develop the necessary competence, and what is known about the institutions that prepare them? Is there high-quality research to support current methods of preparing teachers or to guide improvements?

COMMITTEE TASK AND REPORT

In response to a mandate from Congress for an objective and comprehensive synthesis of the available evidence on key questions about teacher preparation that could be used as the basis for future policy making, the



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1 Introduction T eachers make a difference. Indeed, of all the factors that education leaders can control, the quality of teaching has perhaps the greatest potential effect (see, e.g., Wenglinsky, 2002; Rockoff, 2004; Rivkin, Hanushek, and Kain, 2005; Clotfelter, Ladd, and Vigdor, 2007). Policy has begun to reflect this perspective, most prominently in the provision of the No Child Left Behind Act of 2001 (NCLB) that requires that all public school teachers in core academic areas be highly qualified by 2012. Teacher qualifications and preparation are likely to remain in focus even as the policy environment for education reform shifts. Yet many questions about what it takes to produce highly qualified teachers, and about how teachers are currently prepared, do not have clear answers. Who enters teaching and what educational options are available to aspiring teachers? What should teachers be required to study? Should all teachers be required to complete a program of professional education, culminating in a university degree? Are U.S. teachers provided with real opportunities to develop the necessary competence, and what is known about the institutions that prepare them? Is there high-quality research to support current methods of preparing teachers or to guide improvements? COMMITTEE TASK AND REPORT In response to a mandate from Congress for an objective and compre- hensive synthesis of the available evidence on key questions about teacher preparation that could be used as the basis for future policy making, the 

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0 PREPARING TEACHERS Institute of Education Sciences of the U.S. Department of Education asked the National Research Council (NRC) to conduct the required study. With additional support from the Kaufmann Foundation, the Carnegie Corpora- tion of New York, and the Spencer Foundation, the NRC established the Committee on the Study of Teacher Preparation Programs in the United States to carry out this work. The committee’s charge was to answer four questions: 1. Who enters teacher preparation programs (preservice, graduate, and alternative)? What is their academic preparation? What is their educational background? 2. What type of instruction and experiences do participants receive in the preparation program? Who delivers it? To what extent is there commonality in content and experiences? 3. To what extent is the required coursework and experiences in read- ing, mathematics, and science across teacher preparation programs consistent with converging scientific evidence? 4. What model for data collection would provide valid and reliable in- formation about the content knowledge, pedagogical competence, and effectiveness of graduates from the various kinds of teacher preparation programs? We interpreted this charge as focusing on public school teachers both because they are the objects of public policy and because the majority of the research on teacher quality and teacher preparation also focuses on them. We recognize the vital contribution that private school teachers make, but more than 85 percent of students in the United States attend public schools.1 Broadly viewed, our charge was to review the scientific evidence that pertains to teacher preparation and to consider the data collection that will best support improvements to this critical element of the public education system. The goal, implicit in our charge, was to rely on findings that are the product of responsible scholarship. We faced several challenges, however. First, the available data relevant to our charge are patchy. Second, the task of applying empirical evidence to some of the questions raised complex conceptual issues, such as the challenge of linking teacher characteristics and preparation to measures of student outcomes. In pursuit of answers, 1 In 2006, more than 49 million students were enrolled in public schools, just over 6 million were enrolled in private schools, and another 1.5 million were home schooled (see http://nces. ed.gov/quicktables/ [January 2010]). Career pathways and preparation for private school teachers may differ in significant ways from those of public school teachers, but these differ- ences are not well documented.

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 INTRODUCTION we explored a wide range of materials, held searching discussions about what inferences could be drawn from different sorts of evidence, and com- missioned reports to delve more deeply into specific questions. The committee had six formal meetings and a range of other interac- tions in the course of our study. We considered presentations from people with a range of expertise and perspectives on methodological issues; on what knowledge, skills, and attributes teachers should have; on the nature of teacher preparation in a variety of jurisdictions; and on the nature of professions. We also held two workshops, one on teacher certification and licensure and the accreditation of teacher preparation programs, and the other on evidence related to the preparation of teachers of mathematics and science. In order to probe more deeply into several of our study questions, we commissioned three additional analyses, two on teacher preparation programs and career pathways in two jurisdictions and one related to data collection. Grossman and colleagues (2008) investigated the specific char- acteristics of teacher preparation and the impact they may have on student achievement in New York City, and Sass (2008) conducted a similar analy- sis for Florida. Crowe (2007) provided an overview of the current state of data systems, data collection, and data quality relevant to the knowledge, skills, and effectiveness of program graduates, which assisted us in respond- ing to the part of our charge that requested recommendations regarding a model for future data collection. Our response to our charge has several parts. The remainder of this chapter provides an overview, covering the characteristics of those who enter the field, a brief history of teacher preparation designed to provide context for current pressing policy and research questions, and a few key points about the circumstances in which today’s teachers work. We were asked a number of factual questions about the current state of scholarship on how teachers ought to be prepared, as well as what is known about how they are currently being prepared. Most of that information is presented in Chapters 3 through 8. Since we were also asked to review the status of data collection and other kinds of research and to develop a framework to guide future work, we turn to that issue first in Chapter 2. The nature of the available lit- erature, as well as conceptual questions about the sorts of inferences the committee could make from different kinds of material, were the subject of far more of the committee’s deliberations than we had expected. These issues are important not only to our own deliberations, but also to a clear understanding of what it will take to improve teacher preparation. In Chapter 3 we present what we have learned about the career path- ways open to teacher candidates and the programs in which they are edu- cated. In Chapters 4 through 7 we present our findings related to content

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2 PREPARING TEACHERS preparation, in response to the second and third questions in our charge. Chapter 4 is an overview of issues that cut across the three school subjects we addressed. Chapters 5, 6, and 7 describe our findings related to read- ing, mathematics, and science, respectively. Chapter 8 examines the issues of accountability and quality control in teaching and their effect on teacher preparation. In Chapter 9 we return to the issues raised in Chapter 2 in presenting our research agenda for the future and our concluding thoughts. A dissent to our report from committee member Michael Podgursky is Appendix A. ONE OF THE LARgEST OCCuPATIONS IN THE uNITED STATES The 3.6 million elementary and secondary public school teachers work- ing in the United States in 2006 made up more than 8.5 percent of all college-educated workers aged 25 to 64 years old (National Center for Edu- cation Statistics, http://nces.ed.gov/programs/digest/d08/tables/dt08_064. asp [November 2009]). By way of comparison, there were approximately 888,000 physicians, 1.0 million lawyers, and 2.9 million registered nurses practicing in the United States in 2007. Approximately 200,000 new teach- ers graduate each year, a pace that far outpaces that in any other profession. For example, just over 16,468 new doctors graduated from 128 medical schools in 2009 (http://www.aamc.org/data/facts/enrollmentgraduate/start. htm [January 2010]). Although professional training is still not a universal requirement for aspiring teachers, by the 1950s it was common for public school teachers to receive at least some preservice professional education in a college or university setting (Fraser, 2007). Yet teacher education has never been standardized as it has been for some other occupations. Teaching has fre- quently been regarded as less than a full profession, and both the study of pedagogy and teacher preparation have been accorded less status than other professional or academic pursuits (National Research Council, 2008a). States’ requirements for teacher qualifications and their governance of teacher preparation vary markedly, as we discuss in later chapters. Thus, like the public education system it serves, teacher preparation continues to be characterized by variation rather than standardization (Labaree, 2004; Fraser, 2007). It is a substantial enterprise nevertheless. In 2004, more than 220,000 students completed a teacher preparation program (U.S. Department of Education, 2006). In 2006, 174,620 master’s degrees were awarded in education, accounting for 29.4 percent of all the master’s degrees awarded that year (National Center for Education Statistics, 2007); master’s degrees in business were the second most numerous, at 142,617. An additional 107,238 education students earned bachelor’s degrees that year, account-

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 INTRODUCTION ing for 7.2 percent of all bachelor’s degrees that year (National Center for Education Statistics, 2007), and many more so-called alternative programs augment the numbers of new teachers.2 Teach for America, a program that recruits recent graduates of the nation’s most elite colleges and universi- ties and provides them with training both before and after they enter the classroom, is perhaps the best known of these. Many school districts have established fellows’ programs, which usually combine expedited entrance into teaching with tuition-supported enrollment in graduate study in edu- cation. There are numerous other models as well—by one count there are 130 pathways identified as “alternative” in the 50 states and the District of Columbia (U.S. Department of Education, 2006). Yet universities still dominate: 70-80 percent of students who completed teacher preparation programs were enrolled in one of 1,096 programs situ- ated in postsecondary institutions (U.S. Department of Education, 2006).3 These programs typically include 4-year bachelor’s degree programs and 1-year postbaccalaureate programs (see Chapter 3). CHARACTERISTICS OF TEACHERS We were asked about the characteristics of those who enter teacher preparation programs and the extent to which their characteristics may vary across programs. We found little systematic information about teacher candidates as they enter preparation programs (see Chapters 5-7 for some program-specific research); more research attention has been paid to the characteristics of new teachers who enter the field. The National Center for Education Statistics recently initiated a longitudinal study of beginning teachers (see http://nces.ed.gov/surveys/btls/ [November 2009]), which will eventually provide information about the career pathways of teachers who have been prepared in different ways. Other sources provide demographic data about teacher education stu- dents and the current public school teaching work force: these data were summarized by Zumwalt and Craig (2005). Confining their attention to studies and survey data published between 1985 and 2004 that used sample sizes and methodologies that were clearly described and strong enough to support their reported conclusions, Zumwalt and Craig were able to as- semble a general picture of current teachers. We note that although this summary reflects data available through 2004, much of the information is from the 1980s and 1990s; we were not able to locate more up-to-date 2 Distinguishing between “alternative” and “traditional” programs is so complex that the labels are no longer useful; see Chapter 3. 3 Chapter 3 includes a more detailed discussion of the challenges of counting teacher prepa- ration programs.

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 PREPARING TEACHERS data. Zumwalt and Craig note that there is a significant time lag in the collection, release, and analysis of data about teachers and that there are significant gaps between data collection points. Because there is no compre- hensive effort to collect data about teacher candidates, information about their characteristics is not precise. For example, Zumwalt and Craig note that because classifications of ethnic groups have changed over the years, they have little confidence even in the limited information they found on this characteristic. The teaching work force remains overwhelmingly female: 75 percent in 2000. Although the percentage of female college graduates choosing to enter teaching dropped from 40 percent in 1970 to 11 percent in 1990, females are likely to continue dominating the field because they make up an even higher proportion (84 percent) of teachers in their 20s. Teacher education students are also overwhelmingly female, and aspiring elemen- tary teachers are more likely to be female than aspiring secondary teachers. Available data provide varying estimates—between 67 and 80 percent—of all teacher education students. Teachers are also predominantly white (84 percent); 7.8 percent are African American, 5.7 percent are Hispanic, 1.6 percent are Asian Ameri- can, and 0.8 percent are Native American. Zumwalt and Craig (2005, p. 114) note that while these proportions have fluctuated slightly, “the diversity gap between students and teachers is large and widening.” This claim is supported by the limited data that are available, which show, for example, that the number of nonwhite students earning bachelor’s degrees in education declined by 50 percent between 1975 and 1982. The proportions of teacher candidates of different ethnic backgrounds differ across regions and institutions: some studies show that alternative programs may attract higher proportions of African American students than traditional programs do. Because students tend to look for postsec- ondary options close to home, the distribution of population subgroups among teacher preparation programs partly reflects the make-up of the regions in which they live. African American students, whose families’ incomes are lower than those of white students, are more likely to attend 2-year programs. In terms of other characteristics, the average age of teacher education students has been increasing slightly, likely reflecting a greater number of postgraduate and alternative options. Teachers’ socioeconomic status, as measured by their parents’ educational attainment, has edged up, as has that of teacher education students, but this trend may simply reflect the increase in overall educational attainment in the United States over time. Data collected by the National Center for Education Statistics (1999) show that almost all teachers have a bachelor’s degree, and that 45 percent have a master’s degree. High school teachers are the most likely to have a degree

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 INTRODUCTION in an academic field, rather than an education degree: 66 percent of high school teachers, 44 percent of middle school teachers, and 22 percent of elementary school teachers. A BRIEF HISTORy OF TEACHER EDuCATION The scale of initial teacher preparation is daunting and highlights the policy challenge of increasing teacher quality. Many of the newer pathways that are now part of the nation’s teacher preparation system were created in response to concerns about teacher quality. But much of the innovation in teacher preparation, whether in university-based programs or in other settings, has not been well documented, and, as discussed below, data have not been systematically collected to support firm conclusions about which programs produce effective teachers. The extreme variation in the way U.S. teachers are prepared reflects the overlapping layers of authority and oversight in a system that has placed education firmly in the jurisdiction of state and local governments. Since Horace Mann took charge of the first state department of education in the Commonwealth of Massachusetts in the 1840s, state departments have added their authority on top of those of local school authorities. Passage of the Elementary and Secondary Education Act of 1965 (ESEA) broke through long-standing opposition to federal involvement in public educa- tion, and, more recently, NCLB, a revision of ESEA, greatly enlarged the federal role. However, the federal government has had little direct involve- ment in or influence on teacher preparation. A brief look at the historical roots of teacher preparation in the United States sheds some light on its current nature and structure. Formal teacher training began with the establishment of normal schools during the mid- 19th century. Between 1839 and 1865, 15 normal schools began operation; by 1890, there were 92 such schools (Lagemann, 2002; Ogren, 2005).4 Beginning in 1879, colleges and universities also started to appoint special professors of pedagogy, and by the turn of the 20th century, universities that supported schools and colleges of education began to compete with normal schools for both aspiring teachers and state funds. Eventually, uni- versities became dominant and normal schools either were incorporated into universities or began their slow evolution into state universities (Jencks and Reisman, 1967; Judge, 1982; Clifford and Guthrie, 1988; Herbst, 1989; Labaree, 2004; Fraser, 2007). Complaints about teachers’ lack of competence—and even ridicule of their shortcomings—date as far back as the colonial era (and are still heard regularly today) (Elsbree, 1939; Sedlak, 1989; Lagemann, 2002). Yet few 4 Normal schools were those set up to prepare high school graduates to be teachers.

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6 PREPARING TEACHERS formal studies of teacher education appeared until early in the 20th century (many sponsored by private philanthropic organizations), and the quality of teaching did not become a matter of intense public policy concern until the 1950s and 1960s. In those years, concern about the lack of rigor in public schools led to challenges to the progressive educational practices that had been adopted in the 1930s. Such books as Educational Wastelands: The Re- treat from Learning in Our Public Schools (Bestor, 1953), The Diminished Mind (Smith, 1954), Education and Freedom (Rickover, 1959), and The Miseducation of American Teachers (Koerner, 1965) offered a pessimistic view of teachers and their preparation. One response came from John W. Gardner, president of the Carnegie Corporation, who asked former Har- vard University President James B. Conant to study teacher preparation and other aspects of public education. Conant (1963) concluded that the problem lay with the education classes teachers were required to take. He advocated that teachers be educated in master’s degree programs, similar to one he had established at Harvard, in which students would study the lib- eral arts and experience supervised practice teaching (Lagemann, 1989). The publication of A Nation at Risk (National Commission on Excel- lence in Education, 1983) initiated the longest sustained period of atten- tion to public education in the nation’s history and ignited a new wave of interest in teacher preparation. Using an alarmist style, the report described deficiencies in the public schools. Although diagnoses of the problem have shifted since the report was published, a consensus emerged that instruc- tion was critical to student achievement and that both teacher quality and preparation needed to be addressed. As a follow-up to that report, the Carnegie Task Force on Teaching as a Profession (1986) issued a report that made a number of recommenda- tions designed to improve the quality of the nation’s teaching force, one of which was to “develop a new professional curriculum in graduate schools of education leading to a Master’s in Teaching degree, based on systematic knowledge of teaching and including internships and residencies in schools (p. 3). The report also called for the establishment of the National Board for Professional Teaching Standards (NBPTS), a body that would certify practicing teachers who meet standards of accomplished teaching (that is, teachers who have moved beyond entry-level skills and knowledge) as part of its broad goal of establishing a more professional environment for teachers and a career trajectory that would reward them for pursuing excellence. The NBPTS has been operating for more than 20 years, but the Carnegie Task Force’s recommendations for teacher education—like those Conant had made earlier—have not been systematically pursued (National Research Council, 2008a). Many other individuals and groups have also

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 INTRODUCTION made recommendations about teacher preparation, yet it remains extremely varied and, as we discuss in subsequent chapters, difficult to characterize. A CHANgINg STuDENT POPuLATION As views of how teachers ought to be prepared have shifted over time, other changes have affected the demands on practicing teachers—and, in turn, expectations for their preparation. We cannot address all of these changes here, but changes in the population of U.S. public school students and in views about the public schools’ responsibility to students with vary- ing needs have had particularly broad implications for teachers’ work. Three changes have been particularly important: a commitment to high standards and college for all, increasing population diversity, and the Indi- viduals with Disabilities Education Act (IDEA) of 1975. The commitment to educate all students—particularly including those from historically underserved groups, such as minorities and students from low-income families—to high standards has had profound implications for public school teachers. The proportion of students graduating from high school grew from less than 10 percent in 1900 to about 75 percent by the 1970s. Today educators are expected to prepare every child to go on to postsecondary education—an idea that would have seemed preposterous 100 years ago (National Research Council, 2001c). Some important implications of this commitment are evident when one contemplates the numbers of children who are living in poverty, including some who are homeless, and the ways in which their circumstances may affect their education.5 High-poverty students are the most likely to be taught by teachers who are not well qualified, in part because high-poverty schools tend to see high teacher turnover (Clotfelter, Ladd, and Vigdor, 2007). Although some teacher preparation programs may focus attention on the needs of poor and homeless children, there are no systematically collected data on the subject. With respect to the nation’s fast-changing demographics, the word “diversity” may have lost some of its impact through overuse, but its impli- cations for public education are very concrete. As the United States has ex- perienced significant increases in immigration in recent decades, the number of young people for whom English is not their first language has grown, as has the geographic dispersion of those young people. Language and cultural diversity is not a new feature of U.S. schools. Education historians point 5 In2006, for example, 17 percent of children were living in families with incomes below the poverty line (see http://www.childtrendsdatabank.org/indicators/4Poverty.cfm [January 2010]), and it is estimated that between 5 and 8 percent of school-age children are homeless (see http://www.endhomelessness.org/content/article/detail/1659 [January 2010]).

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8 PREPARING TEACHERS to large numbers of immigrants in the first decades of the 20th century, es- pecially in urban schools, and note that they had a significant influence on goals for public schooling, such as teaching citizenship, promoting student health, and providing vocational education (Editorial Projects in Education, 2000). However, the numbers, percentages, and geographical distribution of students who are immigrants or the children of recent immigrants have all expanded significantly in recent decades. In 2000, 20 percent of all children under 18 (11 million of the 58 million school-age children) in the United States had parents who were recent immigrants (Capps et al., 2005). As has historically been the case, the children of immigrants are concen- trated in the largest states: California currently has the largest percentage of such children (47 percent), and New York and Texas also have significant percentages of such children and long immigrant traditions (Capps et al., 2005). But other states in regions that had previously had only very small numbers have seen dramatic increases in a very short time. Between 1990 and 2000, for example, Georgia, Illinois, Minnesota, Nevada, and North Carolina saw increases in their language-minority populations of more than 100 percent, and in some cases more than 200 percent. More than half of these students, 55 percent, come from Spanish-speaking countries; the next largest group, 25 percent, is from Asia; and 4 percent are from Africa (Capps et al., 2005). The children of immigrants bring to the classroom a wide range of lan- guage and cultural traditions. Teachers may see these traditions as potential assets, rather than as deficits for learning, but these students nevertheless present challenges for teaching. These children vary in the educational expe- riences they have had prior to entering U.S. schools (if they are immigrants themselves), in their parents’ level of education, and many other factors. A significant number have had their education interrupted—and are now identified as a distinct group, students with interrupted formal education. The majority of students who are English-language learners both live in linguistically isolated families (that is, families in which the adults are also English-language learners) and attend linguistically segregated schools. At the same time, however, many communities are home to students from mul- tiple linguistic backgrounds, so teachers might be responsible for children who are speakers of several different languages in one class. Speakers of dialects in regions around the country also present a challenge for many teachers; that is, some native students speak a “non- standard” English that significantly affects their education. Like English- language learners, these students are likely to be reading below grade level and to lack the necessary vocabulary to succeed in academic subjects. Results from the National Assessment of Educational Progress and other education indicators consistently show that these students do not perform

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 INTRODUCTION as well academically as their peers, and many studies document the deficien- cies in their educational opportunities (Banks et al., 2005). Though many would argue that every form of teacher preparation should incorporate the knowledge and skills needed to teach these stu- dents (Lucas and Grinberg, 2008), preparation in this domain is uneven at present. One study of the 1.2 million teachers (about 43 percent of all teachers) with “emergent bilinguals” (students not yet fluent in English) in their classrooms found that only 11 percent were certified in bilingual education; another 18 percent were certified in teaching English as a second language. On average, these 1.2 millions teachers had received 4 hours of in-service training for working with emergent bilinguals over the previous 5 years (Zehler et al., 2003). (Only 15 percent of these teachers were fluent in another language.) Although there are many challenges that complicate teachers’ work, the diversity of the 21st-century classroom is a central one. The needs of English-language learners are of particular importance to teachers of reading, as we discuss in Chapter 5. The inclusion of many more children with disabilities has been an- other very significant change for U.S. schools. Between 1984 and 1997, high school graduation rates for children with disabilities increased signifi- cantly (see http://www.ed.gov/policy/speced/leg/idea/history.html [November 2009]). Public schools have also moved from accommodating almost no stu- dents with disabilities to accommodating most of them. For these students, 1975 was a landmark year: passage of the Education for All Handicapped Children Act, which mandated that children who were deaf, blind, emo- tionally disturbed, or mentally retarded could no longer be excluded from neighborhood schools. Today, the legislation governing students with disabilities requires spec- ified educational services, mostly provided within a regular school setting. Prior to its enactment, children with disabilities were more likely to be ex- cluded from public education or given only limited access to it. The law was designed to address specific challenges to providing an equitable education for these students, by, for example, requiring the development of individual education plans to meet students’ needs, training for teachers, and programs designed to be relevant for families of different cultural backgrounds with disabled children (U.S. Office of Special Education Programs, no date). In the 2006-2007 school year, 6.7 million children, approximately 9 percent of the population aged 3 to 21 in the United States, were receiving educational services as required by IDEA, and these students comprised approximately 11.5 percent of students enrolled in prekindergarten through 12th grade (National Research Council, 2004; see http://nces.ed.gov/fastfacts/display. asp?id=59 [February 2010]). The needs of the students with disabilities who are served by public schools vary dramatically. One-half have some sort of learning disability,

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20 PREPARING TEACHERS ranging from mild to quite severe. Other disabilities include speech or language impairments, physical disabilities, cognitive disabilities, mild to severe medical and emotional disabilities, and injuries (National Research Council, 2004). Although states and districts vary in their criteria for diag- nosing disabilities and in the specific policies through which they implement the IDEA requirements, it is clear that teachers face far different challenges than they did prior to IDEA and that many teachers are responsible for students with a wide range of disabilities. Overall, the work of teachers has become more and more complex as the nation pursues the goal of equal, and equally high-quality, education for all students.