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Suggested Citation:"B Reference Paper." National Research Council. 2003. Improving Undergraduate Instruction in Science, Technology, Engineering, and Mathematics: Report of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/10711.
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Suggested Citation:"B Reference Paper." National Research Council. 2003. Improving Undergraduate Instruction in Science, Technology, Engineering, and Mathematics: Report of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/10711.
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Suggested Citation:"B Reference Paper." National Research Council. 2003. Improving Undergraduate Instruction in Science, Technology, Engineering, and Mathematics: Report of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/10711.
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Suggested Citation:"B Reference Paper." National Research Council. 2003. Improving Undergraduate Instruction in Science, Technology, Engineering, and Mathematics: Report of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/10711.
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Suggested Citation:"B Reference Paper." National Research Council. 2003. Improving Undergraduate Instruction in Science, Technology, Engineering, and Mathematics: Report of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/10711.
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Suggested Citation:"B Reference Paper." National Research Council. 2003. Improving Undergraduate Instruction in Science, Technology, Engineering, and Mathematics: Report of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/10711.
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Suggested Citation:"B Reference Paper." National Research Council. 2003. Improving Undergraduate Instruction in Science, Technology, Engineering, and Mathematics: Report of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/10711.
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Suggested Citation:"B Reference Paper." National Research Council. 2003. Improving Undergraduate Instruction in Science, Technology, Engineering, and Mathematics: Report of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/10711.
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Suggested Citation:"B Reference Paper." National Research Council. 2003. Improving Undergraduate Instruction in Science, Technology, Engineering, and Mathematics: Report of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/10711.
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Suggested Citation:"B Reference Paper." National Research Council. 2003. Improving Undergraduate Instruction in Science, Technology, Engineering, and Mathematics: Report of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/10711.
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Page 136
Suggested Citation:"B Reference Paper." National Research Council. 2003. Improving Undergraduate Instruction in Science, Technology, Engineering, and Mathematics: Report of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/10711.
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Page 137
Suggested Citation:"B Reference Paper." National Research Council. 2003. Improving Undergraduate Instruction in Science, Technology, Engineering, and Mathematics: Report of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/10711.
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Page 138
Suggested Citation:"B Reference Paper." National Research Council. 2003. Improving Undergraduate Instruction in Science, Technology, Engineering, and Mathematics: Report of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/10711.
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Appendix B Reference Paper 127

Improving Student Learning in Science Through Discipline-Based Education Research Lillian C. McDermott Department of Physics, University of Washington INTRODUCTION conducted by science faculty within science departments. I shall present I would like to thank the Council of some evidence that this is an effective Scientific Society Presidents for the approach for improving student learning 2000 Award for Achievement in Educa- (K–20). The emphasis here will be on tional Research. The accomplishments introductory university students and recognized by this honor are the result K–12 teachers. of many contributions by faculty, postdocs, graduate students, K–12 teachers, and undergraduates in the CONTEXT FOR RESEARCH Physics Education Group at the Univer- sity of Washington. A brief description of the Physics Perhaps my “most seminal research Education Group can set a context for achievement” has been to demonstrate, our research. Our group is an entity in the context of physics, the value of within the Physics Department in the discipline-based education research. same sense that there are groups in This type of research differs from other subfields of physics. The courses traditional education research in that in the department provide the primary the emphasis is not on educational environment for our investigations. theory or methodology in the general Most of our work involves two popula- sense but rather on student understand- tions: undergraduates in the introduc- ing of science content. For both intel- tory calculus-based course and prospec- lectual and practical reasons, discipline- tive and practicing K–12 teachers who based education research must be are taking special courses designed to 129

prepare them to teach physics and PERSPECTIVE ON TEACHING AS A physical science by inquiry. Our investi- SCIENCE gations also include students in engi- neering and in advanced undergraduate The perspective that teaching is a and graduate physics courses. science, as well as an art, motivates our As part of our research on how to work. Considered as a science, teach- improve student learning in physics, we ing is an appropriate field for scholarly try to identify specific difficulties that inquiry by scientists. This view is in students encounter in the study of marked contrast to that held by many various topics. The results are used to science faculty. design instructional materials that A more traditional view was ex- target these difficulties and help guide pressed in 1933 in the first article in the students through the reasoning re- first journal published by the American quired to overcome them and to develop Association of Physics Teachers a coherent conceptual framework. (AAPT). In “Physics is Physics,” F.K. Assessment of effectiveness with Richtmyer (Cornell University) argued students is an integral part of the that teaching is an art and not a science. iterative process through which the He quoted R.A. Millikan (California Physics Education Group develops Institute of Technology) in characteriz- curriculum. To ensure applicability ing science as comprising “a body of beyond our own university, our materi- factual knowledge accepted as correct als are also tested at pilot sites (e.g., by all workers in the field.” Richtmyer Georgetown, Harvard, Illinois, Mary- went on to say: “Without a reasonable land, Purdue). foundation of accepted fact, no subject Our two major curriculum projects can lay claim to the appellation ‘science.’ are Physics by Inquiry (McDermott, If this definition of a science be ac- Shaffer, and Rosenquist, 1996) and cepted—and it seems to me very Tutorials in Introductory Physics sound—then I believe that one must (McDermott, Shaffer, and the Physics admit that in no sense can teaching be Education Group, 1998). The develop- considered a science.” ment of both is guided by research. Although this is a somewhat limited The first is a self-contained, laboratory- definition of science, I would like to based curriculum for the preparation of challenge the implication that it is not K–12 teachers; the second is a supple- possible to build “a reasonable founda- mentary curriculum that can be used in tion of accepted fact” for the teaching of conjunction with any standard text. physics (and, by extension, other 130 I M P R O V I N G U N D E R G R A D U AT E I N S T R U C T I O N

sciences). For example, we have found FOCUS ON THE STUDENT AS A that most people encounter many of the LEARNER same conceptual and reasoning difficul- ties in learning a given body of material. The focus of our research is on the These difficulties can be identified, student as a learner, rather than on the analyzed, and effectively addressed instructor as a teacher. We try to through an iterative process of research, determine the intellectual state of the curriculum development, and instruc- student throughout the process of tion. Both the learning difficulties of instruction. To the degree possible, we students and effective means for ad- try to follow the procedures and rules of dressing them are often generalizable evidence of an experimental science. beyond a particular course, instructor, We conduct our investigations in a or institution. systematic manner and record our If one documents intellectual out- procedures so that they can be repli- comes for student learning, teaching cated. We use two general methods: can be treated as a science. If the individual demonstration interviews criteria for success are clearly stated (which allow deep probing into the and the results are reproducible, find- nature of student difficulties) and ings from research can contribute to “a written tests (which provide information reasonable foundation of accepted fact.” on prevalence). Continuous pre-testing This foundation is represented by a and post-testing enable us to judge the rapidly growing research base. effectiveness of instruction. The personal qualities and style of an Although experienced instructors instructor contribute to the aspect of know there is a gap between what they teaching that can be viewed as an art (a say and what students learn, most do benefit confined to the instructor’s not recognize how large the gap can be. class). However, when student learning The usual means of evaluation in phys- is used as the criterion (as distinct from ics courses—the ability to solve stan- student enthusiasm), we have found dard quantitative problems—is not that effective teaching is not as tightly adequate as a criterion for a functional linked as is often assumed either to self- understanding and unfortunately assessment of learning by students or reinforces the perception of physics as a to their evaluation of the course or collection of facts and formulas. Suc- instructor. cess on numerical problems does not provide adequate feedback for improv- ing instruction. Questions that require APPENDIX B 131

qualitative reasoning and verbal expla- SCIENCE COURSES FOR nations are essential. INTRODUCTORY STUDENTS Our investigations have shown that on certain types of qualitative questions, Introductory science courses should student performance in physics is help students construct basic concepts, essentially the same: before and after integrate them into a coherent concep- standard instruction by lecture and tual framework, and develop the reason- textbook, in algebra-based and calculus- ing ability necessary to apply them in based courses, whether or not there is a situations not explicitly memorized. standard laboratory, whether or not Significant progress toward these goals demonstrations are used, whether is not usually made in a traditional classes are large or small, and regard- course. In particular, scientific reason- less of the proficiency of the instructor ing skills must be expressly cultivated. as a lecturer. The situation has been the Physics instructors present lectures same in introductory mechanics, elec- that include detailed derivations, lucid tricity, magnetism, waves, optics, and explanations, and suitable demonstra- thermodynamics. We have also found tions. However, they often proceed that advanced students often have from where they are now and do not difficulty with qualitative questions on remember where they were (or think introductory physics, as well as on they were) as students. They frequently topics such as special relativity and think of students as younger versions of quantum mechanics. themselves. This approach is not well There is by now ample evidence that matched to an introductory class since teaching by telling is ineffective for fewer than 5 percent of the students will most students. They must be intellectu- major in physics. (The percentages in ally active to develop a functional under- chemistry and biology are a little standing. The instructor of a course higher.) determines the emphasis, motivates Meaningful learning requires active students, and can promote a view of mental engagement. The challenge, science as a human endeavor. However, especially in large courses, is how to he or she cannot do the thinking for the achieve the necessary degree of intel- students. They must do it for them- lectual involvement. Much of our selves. Some are reluctant to do so; research has been directed toward others do not know how. responding to that challenge in ways that are effective not only at our own university but in other instructional 132 I M P R O V I N G U N D E R G R A D U AT E I N S T R U C T I O N

settings as well. We are developing division physics courses emphasize Tutorials in Introductory Physics to mathematical formalism. The breadth engage students actively in learning of topics covered allows little time for physics. acquiring a sound grasp of the underly- ing concepts. In addition to deficiencies in subject SCIENCE COURSES FOR matter preparation, traditional science K–12 TEACHERS courses have another major shortcom- ing. Teachers tend to teach as they Science departments have a major were taught. If taught through lectures, responsibility for the education of K–12 they are likely to teach that way. More- teachers, both prospective and practic- over, this type of instruction is unlikely ing. Many science faculty assume that to lead to an understanding of the this is a role solely for education faculty. nature of science and thus does not help In fact, the only place that the subject prepare teachers to teach science as a matter preparation of teachers can occur process of inquiry. is in science courses. The study of Teachers need to learn (or relearn) educational psychology and methodol- science in a way that is consistent with ogy cannot help teachers develop the how they are expected to teach. For depth of understanding of science more than 25 years, our group has content that they need in order to teach provided that opportunity through effectively. The national effort to special physics courses for prospective improve K–12 science education will not and practicing K–12 teachers. These succeed without the direct involvement classes have provided an environment of science faculty. for research on the preparation needed The courses offered by most science for teaching physics and physical departments do not provide adequate science by inquiry. The results have preparation for K–12 teachers. Descrip- guided the development of Physics by tive courses are useless for preparing Inquiry. elementary and middle school teachers to help students learn basic concepts and reasoning skills. High school RESEARCH AS A GUIDE FOR teachers are not adequately prepared by CURRICULUM DEVELOPMENT: mainstream courses, including the AN EXAMPLE sequence for majors. For example, the traditional introductory physics course Research guides the development of and (to an even greater extent) upper all curricula. The topics in Tutorials in APPENDIX B 133

Introductory Physics respond to the material in their university course or K– questions: Is the standard presentation 12 education.) in textbook and lecture adequate to One part of the question involves a develop a functional understanding? If long-filament bulb, a mask with a small not, what can be done? The illustrative triangular hole (~ 1 cm), and a screen. example below is discussed more fully (See Figure B-1.) For a correct re- in two published articles (Wosilait et al., sponse, students must recognize that 1998; Heron and McDermott, 1998.) light travels in straight lines and that a In teaching geometrical optics, most line source can be treated as a series of instructors begin with the premise that point sources. The image can be found university students have a functional by treating each point on the bulb as a understanding of the rectilinear propa- point source that produces a triangular gation of light. Virtually all students can image on the screen. Since the points state that “light travels in straight lines” are closely spaced, the images overlap and many can elaborate that “light substantially. The result is a vertical travels outward from every point on an rectangle terminating at the top in a object in straight lines.” To determine triangle. whether students can apply these Although the amount of prior instruc- concepts in a simple situation, we tion varied, the results did not. (See designed a written question. Table B-1.) Only about 20 percent of the students answered correctly, either Pretest before or after instruction. About 70 Students were asked to predict the precent predicted that the image would image formed on a screen by various be triangular. In this and many other light sources located in front of a small instances, we have found that certain aperture in a mask. This question has conceptual difficulties are not overcome been given as a pretest to thousands of by traditional instruction. Persistent introductory physics students and to difficulties must be explicitly addressed. more than 100 teaching assistants in our physics Ph.D. program. The question is Tutorial called a “pretest” because it usually The emphasis in the tutorials is on precedes the tutorial that we developed constructing concepts, developing to address the difficulties that the reasoning ability, and relating physics responses of students revealed. (The formalism to the real world, not on question is actually a post-test in that solving standard quantitative problems. students have already had the relevant The tutorials are intended for use in a 134 I M P R O V I N G U N D E R G R A D U AT E I N S T R U C T I O N

Screen Mask with triangular aperture Long-filament bulb (a) (b) FIGURE B-1 Pretest. (a) Students were asked to sketch what they would see on the screen. (b) Correct answer. SOURCE: Wosilait et al. (1998) and Heron and McDermott (1998). Reprinted with permission of the American Association of Physics Teachers and Optical Society of America. small section of about 24 students, in explain up-down and left-right inver- which groups of three or four work sions of images formed by asymmetric together. The structure in these 50- sources. These and other exercises minute sessions is provided by help students recognize how the shape worksheets that guide students through and relative size of the source and a series of exercises and simple experi- aperture and the distances involved ments by asking questions. affect the image. With results from questions like the Systematic monitoring in the class- one described above as a guide, we room helped us improve the tutorial. designed a tutorial entitled Light and One exercise that was added had a Shadow. The tutorial begins by having pronounced effect on student under- students predict the images formed by standing of the geometric model for point and line sources with apertures of light. The students are asked to predict various sizes and shapes. After making what they would see on the screen predictions and explaining their reason- when a frosted light bulb is placed in ing to one another, the students observe front of a mask with a triangular hole. what actually happens and try to resolve Many are surprised to see the inverted any discrepancies with their predictions. image of the bulb. Eventually, they They are then asked to predict and realize that the entire bulb can be APPENDIX B 135

TABLE B-1 Results from Pretest and Posttest Questions Administered in Introductory Physics Courses and Graduate Teaching Seminars Introductory course Graduate seminar Pretests Posttests Pretests (before tutorial) (after tutorial) (before tutorial) (N ≈ 1215) (N ≈ 360) (N ≈ 110) Correct or nearly correct 20% 80% 65% Incorrect: image mimics shape of hole in mask 70% 10% 30% SOURCE: Wosilait et al. (1998) and Heron and McDermott (1998). Reprinted with permission of the American Association of Physics Teachers and Optical Society of America. considered as a collection of point percent drew images the same shape as sources. the aperture, in sharp contrast to the 70 The students recognize that superpo- percent who made this error on the sition of the images from the continuum pretest. (See Table B-1.) of point sources produces an image that The teaching assistants and postdocs closely resembles the extended source, who lead the tutorial sessions partici- but is affected by the shape of the pate in a weekly graduate teaching aperture. They also note that whether a seminar in which they work through the light source can be treated as a point or pretests and tutorials. About 65 percent extended source depends on a variety of have given a correct, or nearly correct, factors. response for the question described above. This result is consistent with our Posttest experience that advanced study may not Throughout the development of the increase student understanding of basic tutorial, assessment played a critical topics. role. In Figure B-2 is one of several We consider the pretest performance posttest questions that we administered of graduate students to be a reasonable on examinations to about 360 students post-test goal for introductory students. in several introductory courses. The As shown in Table B-1, the latter demon- percentage of correct or nearly correct strate a better functional understanding responses was 80 percent, an increase than the graduate students had initially from 20 percent on the pretest. Only 10 had. 136 I M P R O V I N G U N D E R G R A D U AT E I N S T R U C T I O N

Screen Mask with inverted L-shaped aperture Long-filament and O-shaped bulb (a) (b) FIGURE B-2 Posttest question: (a) Students were asked to sketch what they would see on the screen. (b) Correct answer. SOURCE: Wosilait et al. (1998) and Heron and McDermott (1998). Reprinted with permission of the American Association of Physics Teachers and Optical Society of America. COMMENTARY to guide the students in explaining what they saw. He assigned homework It is tempting for instructors to think based on equipment similar to that used that the rectilinear propagation of light in the tutorial. Only about 30 percent of is such a simple concept that only a brief the students responded correctly on the discussion of the topic is needed. homework. The instructor then distrib- Evidence to the contrary comes not only uted solutions. In the regular section, from our own research but from the the instructor did not lecture on the experience of colleagues in our depart- propagation of light through an aper- ment. Recently, instructors of an ture. However, he assigned homework honors section and a regular section of problems that were similar to the the calculus-based course used other instructional sequence in the tutorial. approaches to teach this concept. Their Prompt feedback was given in the form students did not work through the of written solutions. tutorial. Questions similar to the posttest In the honors section, the instructor question in Figure B-2 were posed on demonstrated the image that is formed midterm examinations in both classes. when light from an object passes Only 45 percent of the students in the through a pinhole. He asked questions honors section and 35 percent in the APPENDIX B 137

regular section gave correct, or nearly problems. Moreover, we and others correct, responses. Although the time have found that time spent in this way they spent on this material in lecture does not detract from (and often im- and on homework was not monitored, proves) proficiency in solving standard we do not believe that this factor alone problems. Therefore, increasing the could account for the large difference in emphasis on qualitative reasoning can posttest performance between these help set a higher (yet realistic) standard students and those who had worked for student learning. through the tutorial. (See Table B-1.) It has been our experience that if instruction does not engage students in CONCLUSION confronting and resolving their underly- ing conceptual and reasoning difficul- A major goal of a science course that ties, they do not develop the ability to do is likely to be terminal in the discipline the reasoning necessary to apply con- is to help students recognize whether or cepts to problems that cannot be solved not they understand the basic concepts. by memorized formulas. We attribute In Physics by Inquiry, and to a lesser the success of students who worked extent in Tutorials in Introductory through the tutorial to the detailed Physics, we try to help students learn to knowledge of student difficulties that answer and to ask the kinds of questions informed its development. that are necessary to assess and im- The tutorials are a means of engaging prove their understanding. This ability students intellectually within the con- is critical for all students, but especially straints of large, rapidly paced courses. for those who plan to teach. Learning to More can be achieved if students can go reflect on one’s own thinking transcends through similar material more slowly the learning of physics or any other and thoroughly. Teachers who have science. worked through the development of a Our group has demonstrated that, in ray model for light in Physics by Inquiry the context of physics, discipline-based can deal successfully with more compli- education research can help improve cated combinations of light sources and student learning. Recently, there has apertures. been a steady increase in the number of Research in physics education has physicists who are pursuing this type of shown that the development of a qualita- research. The results are reported at tive understanding greatly improves professional meetings and in articles in student performance on conceptual refereed journals that are readily acces- 138 I M P R O V I N G U N D E R G R A D U AT E I N S T R U C T I O N

sible to physics faculty (McDermott and REFERENCES Redish, 1999). Thus, colleagues who are not involved in education research Heron, P.R.L., and McDermott, L.C. (1998). Bridging the gap between teaching and have a rich resource from which to draw learning in geometrical optics: The role of in developing print and computer-based research. Optics & Photonics News, 9(9), 30–36. McDermott, L.C., and Redish, E.F. (1999). instructional materials. Our experience Resource Letter: PER-1: Physics Education indicates that it is difficult to develop Research. American Journal of Physics, 67(9), 755. effective curriculum that yields consis- McDermott, L.C., Shaffer, P.S., and the Physics tent positive results. Therefore, unless Education Group. (1998). Tutorials in introduc- tory physics. Upper Saddle River, NJ: Prentice- faculty can devote a long-term effort to Hall. the development and refinement of their McDermott, L.C., Shaffer, P.S., and Rosenquist, own instructional materials, they should M.L. (1996). Physics by inquiry (Vols. I-II). New York: Wiley. take advantage of already existing Wosilait, K., Heron, P.R.L., Shaffer, P.S., and curriculum that has been carefully McDermott, L.C. (1998). Development and assessment of a research-based tutorial on designed and thoroughly assessed. light and shadow. American Journal of Physics, Without a research base on student 66(10), 906–913. learning, we lack the knowledge neces- sary to make cumulative progress in improving instruction. There is a need ACKNOWLEDGMENTS in all the sciences for research on the intellectual development of students as Special thanks are due to the current they progress through a given body of faculty in the Physics Education Group: material. Investigations of this type Paula R.L. Heron, Peter S. Shaffer, and demand a depth of understanding that Stamatis Vokos. In addition to past and ordinarily is found only among special- present members of our group, I want to ists in a field. Therefore, such research express my appreciation to the past and must be conducted by science faculty in present leadership of the Physics the context of courses offered by Department and the University of science departments. Washington. I would like to recognize The American Physical Society has the early intellectual influence of Arnold issued a statement in support of re- B. Arons and the contributions by our search in physics education as a schol- physics colleagues here and elsewhere. arly activity by faculty in physics depart- I am also grateful to the National Sci- ments. By taking similar action, other ence Foundation for enabling our group scientific societies could help to do the research for which this CSSP strengthen efforts to improve student Award is being given. learning in their disciplines. APPENDIX B 139

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Participants in this workshop were asked to explore three related questions: (1) how to create measures of undergraduate learning in STEM courses; (2) how such measures might be organized into a framework of criteria and benchmarks to assess instruction; and (3) how such a framework might be used at the institutional level to assess STEM courses and curricula to promote ongoing improvements. The following issues were highlighted:

  • Effective science instruction identifies explicit, measurable learning objectives.
  • Effective teaching assists students in reconciling their incomplete or erroneous preconceptions with new knowledge.
  • Instruction that is limited to passive delivery of information requiring memorization of lecture and text contents is likely to be unsuccessful in eliciting desired learning outcomes.
  • Models of effective instruction that promote conceptual understanding in students and the ability of the learner to apply knowledge in new situations are available.
  • Institutions need better assessment tools for evaluating course design and effective instruction.
  • Deans and department chairs often fail to recognize measures they have at their disposal to enhance incentives for improving education.

Much is still to be learned from research into how to improve instruction in ways that enhance student learning.

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