Published in the American Physical Society’s Forum on Education Newsletter, Summer 2010, pp. 9-11.

A Better Way to Increase Physics Majors: Greater Emphasis on Concepts

Art Hobson

    I applaud Stewart Brekke’s suggestion [1] that we increase the number of college physics majors by vigorously reaching out to the minorities, women, and inner city kids who have been insufficiently represented in professional physics. As Brekke says, the most important vehicle for accomplishing this is high school physics.

However, Brekke’s solution is “the standard, mathematically-based high school course using drills and practice, especially in physics problem solving, with extra help from the high school physics teacher.” Three lines of evidence suggest that such a course will not solve the problem posed by Brekke and that the best sequence for non-science students is conceptual physics first (no algebra, but quantitative nevertheless). Science students should begin with either an all-conceptual course or an algebra-based but still strongly conceptual course.

First, the recent successful growth areas for high school physics have been conceptual courses first, honors and AP courses second, and traditional math-based courses not at all; women and minorities, in particular, are enrolling in the rapidly-growing conceptual course. According to data from American Institute of Physics education director Jack Hehn and AIP senior research associate Michael Neuschatz, conceptual physics grew by 1,000% during 1987-2005, honors and AP physics grew by 225%, while the standard math-based course remained about constant (2% growth) [2]. Neuschatz attributes the recent overall 76% surge in high school physics enrollments to the “wider variety of physics courses now available to students,” adding that “a higher percentage of students than ever before is now taking conceptual, or non-computational, physics classes, as well as honors and AP physics classes” [3]. According to Hehn and Neuschatz, “It was particularly the spread of the conceptual approach, aimed explicitly at non-science-oriented students who might not yet have the mathematical skills for a traditional course based on algebra and trigonometry, that spurred high-school physics to grow beyond its traditional confines. …From 1987 to 1997, more than two-thirds of the increase in physics enrollments was accounted for by the jump in the number of girls taking physics. And from 1997 to 2001, close to half of the absolute enrollment gain was due to increasing minority participation” [2].

Second, a leading finding of physics education research is that many students who are able to use formulas to solve standard math-based physics problems do not understand the conceptual physics behind these problems. Conventional problem-oriented physics instruction does little to change these misunderstandings [4]-[6]. Thus, effective teaching requires something more conceptual than the traditional problem-solving course. Inquiry-based teaching methods (another key recommendation of physics education research) clearly helps. Brekke’s suggested “extra help from the …teacher” is another good idea. But can these help enough to attract and keep large numbers of minorities, women, and other students who have not previously been attracted to physics, absent a change in course content toward a more conceptual approach?

Third, the College Board, which oversees the Advanced Placement courses and exams, has always urged that students headed for scientific careers complete a conceptual or “Category A” physics course in the ninth or tenth grade before enrolling in an AP Category B (algebra-based) or C (calculus based) course: “A high school version of a Category A course that concentrates on conceptual development and that provides an enriching laboratory experience may be taken by students in the ninth or tenth grade and should provide the first course in physics that prepares them for a more mathematically rigorous AP Physics B or C course” [7]. But students are unfortunately skipping the Category A course and going directly to the mathematical courses. According to a study of AP math and science courses, many students are poorly prepared before starting these courses, some having skipped intermediate preparatory courses so that they could squeeze more AP courses onto their high school transcripts. According to Haverford College physics professor Jerry Gollub, who co-chaired the study group, “They’ve gotten caught up by the success of a system that is being driven by a funny motivation: student efforts to get into college,” rather than knowledge [8].

Thus there is ample reason for non-scientists to enroll in a conceptual physics course first, before possibly proceeding to a more mathematical course. For future science students, there might be another viable path in the future, one that also emphasizes conceptual development. There are plans to introduce a revised AP Category B course, with a recommended two-year syllabus containing a much stronger conceptual component. The first semester of this course might then be a suitable first physics course for scientists. This course should also be suitable as the second physics course for those “cross-over” students who, upon taking a conceptual course, find they are attracted to science.

An even more important reason for urging a more conceptual approach is that today’s typical high school and college curricula fail to provide the scientific literacy that all students so dearly need. The present math-based courses spend little time on modern (i.e. since 1900) or contemporary physics, such as the beautiful new cosmology that is beginning to answer questions that humankind has asked for thousands and probably millions of years. These courses thus fail to describe the physics of the real universe as scientists understand it today. Furthermore, the math-based courses provide little connection to the many physics-related societal topics, such as global warming, that will determine humankind’s future. In this scientific age, all people surely need an enlightened view of the actual physical universe and science-related social issues. Because conceptual physics courses don’t need to spend time on algebraic formulations and problems, it’s possible for these courses to include contemporary physics and societal topics. It’s my understanding (although I haven’t seen the syllabus) that contemporary physics and societal topics will also be addressed in the future in the recommended new two-year AP Category B course.

The minorities, women, and inner city kids about whom Brekke is rightly concerned will be mostly alienated by his recommended algebraic-problem-oriented course, although a few might be attracted by the one-on-one tutoring that he admirably suggests. These students are far more likely to be attracted to a socially relevant and scientifically up-to-date course that avoids algebra. The enrollment figures given above provide evidence for this. Although it’s only anecdotal evidence, I’ve found that such students lose heart and interest right away when I introduce a little algebra into my university-level conceptual physics course, but that they perk up when the course presents, conceptually, the big ideas of classical and modern physics along with related societal topics. This is true not only of minorities, women, and inner city kids, but also of nearly every non-science student I’ve known in 35 years of developing and teaching physics literacy.

I conclude that non-science high school students should begin their study of physics with a broad, conceptual, scientific literacy course that covers the main classical principles, emphasizes modern and contemporary physics, and includes physics-related social issues. The important “second tier” of students that Brekke is interested in, namely students who don’t initially plan to be scientists but who might be persuaded into physics with the right teaching, might then be sufficiently attracted to physics to take an honors or AP high school course following the conceptual course, and/or they might choose physics or engineering once they get to college. This sequence should substantially increase the number of physics majors by attracting Brekke’s “second tier,” while boosting their scientific literacy. Science students should also begin with a first physics course that’s grounded in concepts, either through an all-conceptual first course or through a more mathematical first course that highlights the concepts while including societal and modern topics.

Acknowledgement

My friend and colleague Gay Stewart provided helpful comments.

References:

[1] Brekke, Stewart E., “How to increase the number of physics majors,” FEd Newsletter, Spring 2010, 6-7.

[2] Hehn, Jack and Neuschatz, Michael, “Physics for all? A million and counting!” Physics Today 59, 37-43 (Feb. 2006).

[3] Brinton, Turner “High school physics enrollment hits record high,” American Institute of Physics, Jan. 10, 2007, http://www.eurekalert.org/pub_releases/2007-01/aiop-hsp011007.php.

[4] Mazur, Eric, Peer Instruction, (Prentice Hall, Upper Saddle River, NJ, 1997), Chapter 1.

[5] Kim, Eunsook and Pak, Sung-Jae, “Students do not overcome conceptual difficulties after solving 1000 traditional problems,” Am. J. of Physics 70, 759-765 (July 2002).

[6] Hestenes, David, et al, “Force Concept Inventory,” Phys. Teach. 30, 141-158.

[7]”College Board AP Physics, Course Description, May 2010-May 2011,” p. 5. Available at http://www.collegeboard.com/student/testing/ap/sub_physb.html?physicsb (click on “Download the Course Description”).

[8] Learning and Understanding: Improving Advanced Study of Mathematics and Science in U.S. High Schools, The National Academies Press (2002), available at http://www.nap.edu/catalog.php?record_id=10129. Also Arenson, Karen, The New York Times, “Study faults advanced-placement courses,” Feb. 15, 2002.

Art Hobson (ahobson@uark.edu) is Professor Emeritus of Physics, University of Arkansas, Fayetteville. He is author of Physics: Concepts & Connections (Pearson/Addison-Wesley, San Francisco, 5th edition 2010), a conceptual physics literacy textbook for college students.