Eric Mazurís contribution began with a video showing the U.S. Senate Majority Leader discussing how he wasted his time studying physics, shown in order to demonstrate the urgency of improving our students' experiences in physics. He then proceeded to demonstrate the use of peer instruction, which actively involves the students in the teaching process, can easily be adapted to fit individual lecture styles, and makes physics not only more accessible for students but also easier to teach. The method has been shown to improve students' conceptual learning at a wide variety of institutions.

This work is described in detail in Peer Instruction by Eric Mazur (Prentice Hall, 1997).

We are being asked to change the way we teach. Instead of only training top research scientists (and trashing the rest) we are now being held responsible for adding value to all of our students. What we have to offer our students is a good understanding of the physical world and powerful, complex problem solving skills. To help more of our students reach these goals, we need to help them develop a good functional understanding of physics -- to build a coherent mental model. Few introductory physics students currently do this successfully. If we are to be more effective with more of our students -- especially with those who do not resemble research physicists, we need to understand how they think. This talk reviews some general principles, built from understandings developed in cognitive psychology and education, that can help us to understand some of the "strange" responses we often get from our introductory students. We learn such principles as:

- Learning is better described as a growth than a transfer.

- Cognitive response is context dependent.

-Transfer is non-trivial -- even among isomorphic situations.

- It isn't enough to get them to know the right answer, they have to
also get rid of the wrong answers.

- Students frequently can solve complex algorithmic problems without
having a good understanding of the physics.

In this talk, we present a number of results from research into student understanding in introductory physics, showing how these cognitive principles are reflected in student performance in real classrooms. New methods of evaluating student understanding are discussed and applied to some innovative instructional models.

The slides from this talk are available on the web at URL

http://www.physics.umd.edu/rgroups/ripe/talks/chairs/

Related talks, papers, and information may be found at URLs http://physics.umd.edu/rgroups/ripe/efr/redish.html (Redish homepage) and

http://www.physics.umd.edu/rgroups/ripe/perg/ (University of Maryland at College Park, Physics Education Research Group homepage)

Most physics instructors are aware that only a very few students (< 5%) in an introductory university physics course will major in the subject and the number who go on to graduate study is many times smaller. Not all realize, however, that we are in a much better position today than ever before to increase the likelihood that the study of physics will contribute to the intellectual growth of our students. This possibility exists both for our majors and for the much larger number of students who take the subject to fulfill a professional or distribution requirement. The most significant difference between the present situation and previous reform efforts is the growing body of knowledge about student understanding in physics. Research on the learning and teaching of physics is a relatively new field for scholarly inquiry.

During the past two decades, a steadily increasing amount of research on the learning and teaching of physics has provided a rich resource for the development of curriculum¹. As implemented by the Physics Education Group at the University of Washington, the process of using research to guide curriculum development has three interrelated parts: (1) conducting systematic investigations of student understanding; (2) applying the results in the development of instructional strategies to address specific difficulties; and (3) designing, testing, modifying, and revising the materials in a continuous cycle on the basis of classroom experience with the target population².

Investigations conducted among introductory physics students indicate that the gap between what is taught and what is learned is much greater than most instructors realize. Evidence from research indicates that, on certain types of qualitative questions, student performance is essentially the same: before and after instruction, in calculus-based and algebra-based physics, with and without standard laboratory, with and without demonstrations, in large and small classes, and regardless of the proficiency of the lecturer³.

In a typical introductory course, securing the intellectual engagement of students is a challenging task. To promote active learning, the Physics Education Group is developing Tutorials in Introductory Physics, a set of instructional materials that supplement, but do not replace, the lectures and textbook through which physics is traditionally taught⁴. The tutorials comprise an integrated system of pretests, worksheets, homework assignments, and course examinations. The pretests are usually administered after the material has been covered in lecture and always before the related tutorial. They inform the instructors about the level of student understanding and help the students identify what they are expected to learn in the tutorial session that they will attend that week.

During a tutorial session, 20 - 24 students work in collaborative groups of three or four. They proceed step-by-step through the worksheets that provide the structure for the tutorial. The worksheets consist of carefully sequenced tasks that guide students through the reasoning needed to develop a sound qualitative understanding of important concepts. The tutorial instructors do not lecture but ask questions designed to help students find their own answers. Tutorial homework assignments help students reinforce and extend what they have learned. All course examinations contain questions based on the tutorials. The tutorial system is tightly linked to a required graduate teaching seminar in which ongoing preparation of the tutorial instructors takes place on a weekly basis.

Many of the tutorials are expressly intended to target conceptual and reasoning difficulties that have been identified through research. In designing a tutorial sequence, we frequently employ an instructional strategy that involves a conceptual conflict. The procedure can be summarized as a series of steps: elicit, confront, and resolve.⁵ One effective way of eliciting a known difficulty is to have students commit to a prediction before making an observation. The contradiction between a prediction and subsequent observation provides an opportunity to help students recognize an underlying misconception or inconsistency in reasoning. The tendency to make certain kinds of errors is often elicited by the pretest and tutorial worksheet. The tutorial and associated homework engage students actively in confronting and resolving specific difficulties that impede the development of a functional understanding of the material.

The role of the instructor is to help students by asking questions, rather than by simply giving answers. To teach in this way requires a deep understanding of the subject matter, knowledge of the intellectual state of students, and skill in asking appropriate questions. Most of the tutorial instructors are graduate Teaching Assistants (TA's) enrolled in the physics Ph.D. program. The rest are undergraduate physics majors, M.S. students, post-doc volunteers and a few faculty.

Preparation of the instructional staff takes place weekly in a required graduate teaching seminar. It is well known that most instructors tend to teach as they have been taught. Therefore, the seminar is conducted on the same material and in the same manner as the tutorial sessions. The participants go through the same sequence of activities as will the undergraduates later in the week.

At the beginning of the seminar, the participants take the pretest that was administered earlier in the day in the introductory course. Data from the pretests indicate that graduate students often have some of the same conceptual and reasoning difficulties as undergraduates⁶. The evidence demonstrates that advanced study in physics does not necessarily promote the development of a functional understanding of introductory topics. After taking the pretest, the participants examine the student pretests and try to identify common errors. Working collaboratively in small groups, they then go through the tutorial worksheets step-by-step. Experienced TA's engage the seminar participants in the same type of instruction through questioning that they will be expected to use in the tutorial sessions. Discussions of appropriate instructional strategies for addressing student difficulties arise naturally in this setting.

The tutorials can also be used to enrich student learning in institutions varying greatly in size and mission⁷. The instructional program that has been described is only one of several ways. The important feature that these have in common is the active involvement of the student at a sufficiently deep intellectual level that meaningful learning can occur. We have found that the tutorial system is particularly well-suited to the needs and constraints of a research-oriented physics department. It makes possible some degree of individualized instruction for students in large classes and provides a structure for faculty whose teaching assignments may rotate frequently. The tutorials are not as dependent as some methods on the charismatic qualities of a particular instructor. The tutorials, which are heavily dependent on the preparation of teaching assistants, provide both a strong incentive and an excellent environment for the rigorous preparation of teaching assistants.

For cumulative improvement of physics instruction to occur, individual efforts based on trial and error will not suffice. As is the case with most other academic aspects of university life, scholarly inquiry should play an important role. There is a need for ongoing, systematic investigation into the nature of student difficulties throughout the physics curriculum but especially in introductory courses. These contributions to the research base should not be limited to the identification and analysis of difficulties but should also include descriptions of instructional strategies that have been demonstrated to be effective. If experience has shown that certain methods appear not to work, then this information should also be reported. Relatively little attention has been directed toward assessment of the effect of specific instructional strategies on student learning. It is necessary to examine the intellectual impact on students and to ascertain in a rigorous manner whether the use of a particular instructional strategy brings about a real gain in student learning. This type of research can only be conducted by physicists who have thought deeply about the subject matter, who have had experience in teaching the material, and who are willing to listen carefully to students as a starting point for bridging the gap between teaching and learning.

Two of the classroom sessions that followed the three plenary talks were conducted by Lillian C. McDermott and the Physics Education Group. The purpose was to illustrate how the tutorials described in one of the talks can promote the intellectual engagement of students¹. In each workshop, the participants worked through a tutorial from Tutorials in Introductory Physics, a set of research-based instructional materials developed by the group to supplement the lectures and textbook of a standard introductory course. The workshops were conducted in the same way as the undergraduate tutorial sessions and the graduate teaching seminars in which TA preparation at the University of Washington takes place. The participants worked in small groups on tutorial worksheets designed to address conceptual and reasoning difficulties identified through research.

The tutorial Electric Circuits guides students through the process of constructing a conceptual model for electric current from direct experience with simple circuits consisting of batteries, bulbs, and wires. The observations they make form the basis for a scientific model that can be used to predict and explain the behavior of simple electric circuits. In the tutorial Light and Shadow, students make observations using bulbs, masks, and screens. They use the ideas developed in this context to account for various phenomena, such as the formation of images and shadows due to extended sources. The role of research in the development of these tutorials has been described in articles².

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