Modern society depends on advanced technology. Decisions ranging from the purchase of an energy-efficient air conditioner to legislation on nuclear power plants now routinely confront the public. Almost all technology is based on scientific principles, and providing people with technical knowledge and scientific literacy in a range of fields is one of the most important missions of the physics community. An education accessible and engaging to a broad spectrum of students at all levels is essential for this mission.
Graduates who have specialized in physics provide a unique component of the technical workforce. With their problem-solving skills and grasp of the principles of physics, they are able to attack a wide variety of problems. A well-trained physicist is capable of moving quickly among different technical areas, particularly into areas so new that they have not yet evolved into an engineering discipline. This ability of physicists to solve problems in a wide variety of fields is illustrated by the number of physicists-by-training who have gone on to win Nobel Prizes in other disciplines—for example, Allan Cormak, Francis Crick, Max Delbruck, Godfrey Hounsfield, and Rosalyn Yalow won in physiology or medicine; Marie Curie, Walter Gilbert, Walter Kohn, Ernest Rutherford, and Alan Heeger won in chemistry; and Andrei Sakharov won for peace.
Physics education must meet the needs of several diverse groups. The general public must have the background they need to understand and foster the progress of science. Industry requires a workforce trained in a wide variety of engineering and science disciplines, all of which are founded on physics principles. And research physicists, scientists who advance knowledge in physics itself, require a lengthy and specialized education.
Meeting these goals has proven to be a difficult task. Enrollment in physics courses declines dramatically as students advance through the edu-
cational system, with only about a quarter of students taking a high school physics course. At the university level, physics courses are most often taken as a foundation for study in engineering, medicine, and other sciences and rarely by students in other disciplines. Advanced undergraduate study in physics is undertaken by only a very small number of students, but they are fairly likely to pursue graduate study. In 1999, 31 percent of university and college physics graduates entered graduate programs in physics while an additional 19 percent went into other graduate programs (primarily engineering).
The post-World War II enthusiasm for physics resulted in tremendous interest in the study of physics and expansion of the capacity for physics education in colleges and universities. The space program, which followed the shock of Sputnik and crested with the success of the Moon landing, was accompanied by significant efforts to reform physics education at all levels as well as to expand capacity. The physics community worried that not enough was being done to educate the general public and that its service mission to other academic departments was not being fulfilled. In the early 1980s, the American Association of Physics Teachers, the American Institute of Physics, and the American Physical Society began working together to sponsor programs in support of educational reforms.
An encouraging trend over the past decade was the steady increase in the number of women involved in physics at all levels ( Figure 5.1 and Figure 5.2). High school physics courses now have nearly equal male and female enrollments. Unfortunately, the attrition rate at each stage in the educational process up to the Ph.D. level has remained high. The fraction of Ph.D. degrees awarded to women is only 13 percent. It is particularly troubling that physics seems to be lagging other disciplines such as chemistry and mathematics in the elimination of the gender discrepancy.
The representation of most U.S.-citizen ethnic minorities in physics shows a pattern similar to that for women, although the fractions are smaller. There has been a steady increase in the number of minorities receiving degrees in physics, but the overall numbers are small and drop off dramatically the higher up one looks on the educational ladder.
As society becomes ever more dependent on technology, as physics and the other sciences grow closer together, and as physics itself becomes more ambitious and demanding, physics education must change. Beginning with K-12 physics, continuing through college and university physics, and on through graduate and postgraduate education and training, physics education must meet the needs of the general public, the technical workforce, and the research community.
Good preparation in science at the K-12 level is a prerequisite to good science education at all levels. Physics education begins as part of general science in grade schools and becomes increasingly specialized as the grade levels increase. Typically, a course labeled “physics” has been an option taken late in high school. During the 1970s and 1980s, there was a significant decline in the percentage of students who were studying physics in high schools. In the past decade that decline has reversed itself (see Figure 5.3).
Several studies have documented the problems with education in the physical sciences at the K-12 level. One is the Third International Mathematics and Science Study (TIMSS), which carried out detailed comparisons between the ways students are taught mathematics and science in different
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countries and how they perform on a number of exams. Students in the United States are particularly weak in their understanding of physical sciences at all grade levels, and this is dramatically worse at the higher grades. U.S. students who have had a high school physics course score lower on tests of understanding of physics than comparable students of any other country evaluated. TIMSS characterized U.S. teaching as primarily “learning terms (definitions) and practicing procedures.” Conspicuously absent is the teaching of the nature of the scientific process and the concepts of physics as they apply to the world around us. These are the elements of science education most important for a technically literate society and workforce.
Results such as those from TIMMS have led to concern about the preparation of K-12 science teachers, in particular their background in the discipline they are teaching. Only about a third of the U.S. physics teachers majored in either physics (22 percent) or physics education (11 percent), with many of the others having majored in another science or mathematics ( Figure 5.4). This is a significant problem, because a lack of knowledge of the material is frequently cited as a contributor to poor teaching. One reason for the relatively weak training in physics of K-12 teachers is probably the minor role that physics departments now play in the training. The
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responsibility for this training is largely in the hands of the education schools, and with rare exceptions they have little connection with the physics departments. There is a growing sentiment that teachers can be better prepared by giving physicists a greater role in the process. Implementing this approach will require the encouragement and cooperation of university administrations and education schools as well as changes within the physics departments. The importance of these changes was recognized in resolutions adopted independently by the American Institute of Physics, the American Physical Society, and the American Association of Physics Teachers. The resolutions encouraged physics departments to take increased responsibility for the education of teachers.
In addition to taking a greater role in preparing future teachers, physics departments can contribute to K-12 education by providing ongoing training and assistance to current K-12 teachers. Although many isolated local efforts do this, there is a need for broader programs. The mathematics community has convinced the National Science Foundation (NSF) to fund a faculty member in selected mathematics departments whose main role is to interface with the high school teacher and student community. This is one possible model. Another is the establishment of programs such as the Physics Teaching Resource Agents (PTRA). A cadre of highly qualified and highly trained high school teachers, the PTRA worked with colleagues from higher education to reach out to the majority of those teaching physics who did not have a background in physics. Prominent physicists from our universities and national laboratories have also become involved in local programs reaching out to high school teachers and students. Programs that provide research experiences for K-12 teachers, such as NSF's Research Experiences for Teachers program, can be very effective. They can convey the excitement of real research to teachers and, through them, to even larger numbers of students. All these programs require adequate release time for teachers to take full advantage of them.
In the scientific community and in the leadership of many universities, there is growing concern about the decreasing numbers of students majoring in science. Seymour and Hewitt 1 have studied the reasons for the high
1 E. Seymour and N. Hewitt. 1997. Talking About Leaving: Why Undergraduates Leave the Sciences. Westview Press, Boulder, Colo.
attrition rates for students who enter college intending to major in science. The attrition rate of greater than 60 percent for physical sciences is considerably higher than for any other major ( Figure 5.5). They find no evidence that the students who switch to nonscience majors are less capable than those who do not switch or that inadequate high school preparation is a more serious concern for students who switch than for those who continue. However, a factor that does cause students to switch to other majors is the perception that these alternative majors provide a better education and are more intrinsically interesting.
It is notable that the factors causing women and ethnic minorities to switch out of pursuing science careers are similar to those motivating all students to switch, but the effect of these factors, and hence the attrition rates, seems to be magnified for these underrepresented groups.
Physics is often singled out for particular criticism. Sheila Tobias documented how introductory physics courses deterred many who took them
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and did not continue in physics. 2 She selected her sample population from those who became successful in other areas. She also recruited highly educated volunteers to take introductory physics courses and to report on their experiences. She paints a compelling picture of introductory courses that do not encourage the further study of physics.
Excellent introductory physics courses are important for all students, from those planning to become professional physicists to those majoring in the arts and humanities. Physics also plays a foundational role in the other fields of natural science. Even where the full rigor of physics is not applicable, the approach of physics to characterizing and analyzing problems can be very useful. Every field of natural science and engineering has made use of the instrumentation and experimental techniques developed by physicists; these techniques are an essential part of a physics education.
Over the past two decades, the American Physical Society, the American Institute of Physics, and the American Association of Physics Teachers, among others, devoted much attention to problems in introductory physics courses. Research in physics education began to demonstrate that students were not learning physics as well as had been hoped or expected. Many of the reports and projects began to call for revisions of the curriculum that would do the following:
Take account of research findings on physics education.
Introduce modern, topical physics earlier in the undergraduate curriculum. Make connections to other areas of science.
Focus more on concepts and discovery rather than covering a prescribed set of topics.
The research underlying many of the reform efforts called for more interactive forms of instruction (“active engagement” was a term used). The approach gained momentum after the introduction of a test of the conceptual understanding of mechanics that became known as the Force Concept Inventory. This test and its successors allowed faculty to compare innova-
2 Sheila Tobias. 1990. They're Not Dumb, They're Different: Stalking the Second Tier. Research Corp., Tucson, Ariz.
tions through a system of pre- and post-testing of students that revealed the differential learning gains.
The results of these tests of physics learning often surprised physics faculty, who had assumed that students were learning far more than they actually did. In the various interactive learning formats, the instructors often became aware of student difficulties that they had not observed in the less interactive lecture format. It was important to be able to document student performance in the traditional lecture courses so that student difficulties would not be (erroneously) attributed to the interactive formats. The existence of a body of data covering students at quality institutions all across the country helped to set a baseline for evaluating the new programs.
Introductory physics courses at the universities come in several varieties. One way to classify them is by the level of mathematical sophistication involved. Large universities often offer a spectrum of courses that can be characterized as follows: conceptual physics (no mathematics or minimal mathematics), college physics (trigonometry-based), and calculus-based university physics. Introductory courses are sometimes tailored to the needs of different majors, with the predominant course of that kind being the engineering physics course. Other majors that are often addressed separately include the medical and life sciences, architecture, and the liberal arts. The diversity of offerings belies the similarity in content, coverage, and approach that characterized introductory physics education throughout the last century and up through the present. The texts for these introductory courses all tend to have much the same logical development and subject coverage and changed little over the course of the 20th century.
In 1987, the American Institute of Physics launched the Introductory University Physics Project (IUPP) to recommend alternative approaches. The IUPP focused on content, coverage, and order rather than on pedagogical approaches and alternative methods of organizing instruction. Efforts to include modern physics topics such as quantum mechanics, particle physics, and condensed matter physics were an important part of this project.
Over the past few years, a number of curricula have been developed in the United States using the research/curriculum reform/instruction cycle. Classes based on this approach (“active engagement” classes) have in common a focus on what the students actually do and what the effect of that activity is. An excellent example is Physics by Inquiry, a model developed by the University of Washington that has set a standard for others to aspire to. This discovery-learning, research-based curriculum has gone through 20 years of development and testing. It guides students through the reason
ing and construction of scientific ideas through hands-on laboratory experience. A few generic models for active engagement classes follow, along with specific examples of courses:
– Physics by Inquiry
– Workshop Physics (Dickinson College)
– The Physics Studio (Rensselaer Polytechnic Institute)
– Tools for Scientific Thinking (University of Oregon)
– RealTime Physics (University of Oregon and Dickinson College)
– Active Learning Physics System (Ohio State University)
– Peer Instruction/ConcepTests (Harvard University)
– Interactive Demos (University of Oregon)
– Cooperative Problem Solving (University of Minnesota)
– Tutorials in Introductory Physics (University of Washington)
– Mathematical Tutorials (University of Maryland).
Departments can begin to draw on this experience by determining what they want their courses to accomplish and critically evaluating whether or not they are achieving it. As part of this evaluation they could benchmark their introductory programs against the leading innovative programs and revise their offerings as appropriate. Questions that need to be answered include the following:
Are students actively engaged in doing physics rather than watching the instructor?
Do students in introductory courses gain an appreciation for physics as it is done today?
Does the introductory course take advantage of the computing and communication tools available today?
Do students leave the class with a sense of the excitement of physics, its connection to the other sciences, and how it applies to the world around them? Do they consider further study?
The committee believes that high-quality introductory courses are essential for creating a 21st-century workforce, for fostering scientific literacy, and for attracting and retaining talented American students to further study in physics.
Advanced Undergraduate Programs
With the trend toward incorporating more “modern” physics in the introductory courses and with the increasing sophistication of students in the use of technology, there is an opportunity for physics departments to renew their advanced undergraduate courses. It is important for students to see how physics has contributed to the biomedical sciences and to the growth of information technology. Physics departments would do well to collaborate with their colleagues in other departments to encourage cross-disciplinary experiences and to implement minors and double majors that combine physics and biology, physics and computer science, physics and biomedical engineering, and other novel combinations.
The revolution in information technology and biotechnology has made thousands of scientists into entrepreneurs. For example, Jeff Kodosky, a physics major, cofounded National Instruments based on his vision for how physicists (and other scientists) should be able to interact with scientific instrumentation. Physics departments can work with schools of management to provide physics students with role models and business models for using physics to create new enterprises and new value within existing enterprises (see sidebar “Research Experiences for Undergraduates”).
In physics, teaching and learning flow from research. It is difficult to imagine a proper learning environment for physics students that does not give them extensive exposure to research and physicists engaged in research. These opportunities can be found at major facilities, research centers of various kinds, and research projects under the direction of single investigators. This vision for undergraduate research experience can be more difficult to achieve in smaller liberal arts colleges, but there are indeed opportunities and outstanding examples. The Council for Undergraduate Research was formed specifically to encourage this activity at schools of all sizes. Research universities can, do, and should offer summer and other short-term research experiences to undergraduates from all institutions. Support for this activity can often be built in as supplements to research grants or as targeted funding programs from the NSF.
It can be a challenge to create experiences that benefit both the research effort and the student. Undergraduate students may not have the knowledge to contribute to some aspects of advanced research projects, and it may be difficult to identify tasks that would be meaningful for the project and the student, but physics departments should nonetheless assign a high priority to supporting and integrating students into research projects.
RESEARCH EXPERIENCES FOR UNDERGRADUATES
The most important factor governing the future health of the nation's physics enterprise is the quality of the young people drawn to the field. The undergraduate years are a crucial time in the career paths of potential scientists: These years present the first opportunities for in-depth study that may influence career decisions, convincing potential scientists that the excitement of research and discovery is ample reward for the hard work that science requires.
While there are many community efforts to enhance opportunities for undergraduate research, one of the most successful programs is that begun by the National Science Foundation a decade ago. The NSF Research Experiences for Undergraduates (REU) Program helps interested sites—university departments, government and industrial laboratories, and other research organizations—to recruit undergraduates to take part in individual research projects under the guidance of interested faculty and other senior researchers. The goals also include broadening the talent base in physics and other sciences: Many REU programs have succeeded in increasing participation by women and members of underrepresented minority groups. REU research experiences can be particularly valuable for students coming from smaller colleges that lack the laboratory facilities of larger institutions.
Several thousand students now participate in REU programs in mathematics, science, and engineering. The response by physicists has been particularly strong: More than 100 sites have been created, providing 1000 undergraduate research positions each year. This represents an extraordinary effort by the site directors and the research advisors who give their time to these programs. Most of the sites operate during the summer and provide stipends and housing support for aspiring scientists willing to trade their summer vacations for an opportunity to do research. Below: REU students at LIGO, Hanford, Washington.
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Graduate and postdoctoral physics education programs in the United States are the envy of the world. They are the central sources of high-quality scientific personnel needed to sustain the high levels of achievement that have characterized U.S. physics in all its venues since the end of World War II. Yet physics is changing, and the source and destination of students in the nation's graduate programs are changing also. These changes require corresponding changes in the graduate and postdoctoral education programs, changes that the committee describes below.
The number of U.S.-educated undergraduates in physics has decreased in the last 15 years, leading to an imbalance between the supply of U.S. bachelor's degree holders and the capacity of U.S. graduate programs ( Figure 5.6 and Figure 5.7). Physics departments have reacted by increasing the flow of students from other countries. The committee considers this is a healthy development in view of the anticipated demand. Advantage should be taken of the best talent wherever it may be found. In any case, physics in the United States has always been enriched by this flow of talent from abroad. The flows of physicists from Europe before and immediately after World
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War II, from eastern Europe and the former Soviet Union after the collapse of the latter, and from Asia during the last decade's political unrest in China have all brought highly talented individuals to this country. While celebrating the flow of talent from other countries, the committee also expresses its concern about the significant decrease in the number of U.S. students entering graduate study in physics, reflecting the drop in the number of bachelor's degrees awarded in physics.
The production of Ph.D.'s in physics has been highly volatile over the past 30 years, as has been the demand for them. However, one trend can be clearly identified: An increasing fraction of physics Ph.D.'s find employment in industry. Of the graduates in 1996, 47 percent entered industry while 41 percent entered academia.
Most graduate programs have not changed much from the 1960s and 1970s, when the majority of Ph.D.'s were going into academic teaching and research positions. In the committee's view, the structure of graduate programs should better reflect the changing and varied destinations of students who pursue advanced degrees. Physics departments need to reassess the missions of their graduate programs in light of where the students are headed.
As physics becomes increasingly connected with other sciences and more important in technology development, the committee foresees a growing need for programs that provide training for the majority of students who will not pursue careers in academia. The increasing employment of physicists in industry and the appreciable crossover of physics graduates into other fields support this conclusion.
There is currently a great need for workers with technical expertise, and a graduate physics education is well suited to provide that expertise. Strong physics training provides students with broad problem-solving skills and familiarizes them with a wide range of technologies and the underlying physical principles. This allows them to adapt easily and contribute to many different areas such as electronics, optics, and computational modeling.
Many technical careers do not require training to the degree of specialization or for the extended time (typically 6 years) required to obtain a physics Ph.D. A master's degree would appear to be a more appropriate level of physics education for students interested in working in many high-tech industries. Such training would also be valuable for students planning to work in nonphysics areas that require a good knowledge of physics, such as atmospheric science, radiology, and many types of advanced engineering. While there has been growth in professional master's degrees in areas such as engineering, computer science, and management, physics has not exploited this educational model significantly. Some other opportunities for creating professional master's degrees in physics include the following:
Physics for those going into information-technology-related areas,
Physics for incipient entrepreneurs,
Physics and intellectual property law, and
Physics and the continuing education of engineers and others. />
Physics education at all levels must focus on producing a scientifically literate public and a technically trained workforce. High-quality physics courses are an essential component of science education. They are one of the best avenues to providing the public with the knowledge to make informed scientific decisions, as well as providing technical training for the modern workforce. In addition, these courses are crucial for attracting and retaining capable American students for further study in physics.
Introductory course offerings need to be improved. Educators should take note of innovative teaching methods that have been shown to be effective. Introductory courses are the last exposure to physics that most university graduates will have, so they must lay the physics foundation for further technical training in all areas. For those continuing in physics, the courses must engage students, decrease attrition, and attract new recruits. Courses should be revised so they introduce students to concepts and questions of modern physics, make increased use of advanced computing and communication technologies, and incorporate active physics engagement techniques.
Advanced undergraduate and graduate curricula should reflect physics as it is currently practiced, making appropriate connections to other areas of science, to engineering, and to schools of management. High-quality undergraduate research opportunities are an important tool for introducing students to modern physics practice. Physics education needs to reflect the career destinations of today's students. Only a third of all physics majors pursue graduate degrees in physics, and of those who do, nearly three-quarters will find permanent employment in industry. The undergraduate and graduate curricula must satisfy the educational needs of these students.
The education of K-12 teachers benefits greatly from the involvement of professional physicists. Physics departments can become more involved in the training of high school teachers by offering courses that are geared to the education of future physics teachers and by creating and conducting outreach programs. This conclusion is supported by the broader physics community through the resolutions of the American Physical Society, the American Association of Physics Teachers, and the American Institute of Physics. Achieving each of these goals will be difficult, requiring changes in university physics departments, encouragement from university administrations, and support from state and local education boards.