A case for Problem-based Learning
Introductory physics courses are notoriously filled with a tremendous amount of content, presented in a way that makes sense to physicists, but not to novices. One way to motivate study of physics content is to place it in a real-world context. This allows students to immediately see the relevance and utility of physics, and to introduce mathematical problem solving skills in a way that leads to the answer of a larger question (as opposed to plug and chug).
In the science education literature, this pedagogical approach goes by many names: problem-based learning (PBL), project-based learning, and the case study approach (among others). What all of these techniques share is a desire to motivate students to engage more deeply with the science content. What’s the difference between all of these terms? Problem-based learning is the broad category for this type of teaching, and includes open-ended problem solving, as well as projects and case studies. According to Barrows (1996), the six characteristics of PBL are:
PBL is student-centered.
Students work in small groups.
The instructor (or tutor, as he says) acts as a facilitator or guide.
Authentic problems are used in introduce new content.
Problems are a tool used to develop understanding of new content and problem-solving skills.
New information is acquired through self-directed learning.
As you can see, these criteria could apply to a wide range of teaching strategies. Project-based learning refers specifically to a concrete, tangible product that comes out of the learning process. The project-based learning curricula are typically longer, and provide a structure for the overall course. Case studies refer to a particular type of problem-based learning in which the problem is structured as a narrative. Case studies are typically on the order of one or two class periods, perhaps the length of a lab period (see links below for examples).
Case studies or problems can be drawn from:
Episodes from the history of science. This can be particularly useful in teaching students about the process of scientific inquiry (i.e. nature of science).
Scientific journal articles. These cases give students a sense for what current problems in science and engineering look like, how scientists approach these problems, and what a published article looks like. The case study functions as a translation of an interesting scientific problem put into terms an introductory level student can understand.
Everyday phenomenon. Students are always engaged by problems that they have experienced in their lives. For example, comparing the efficiency of different methods of boiling water.
Current or historical events. This are typically interesting stories that provide a context for learning basic science principles. For example, one case study I have written was about an escape attempts from a Nazi POW camp in World War II. The physics content is in how they launch the glider from the roof of the castle (i.e. kinematics and forces).
Research shows that PBL is effective in developing problem solving skills (e.g. Becerra-Labra et al, 2012; Dochy et al, 2003) and increasing engagement and improving attitude (e.g. Hilvana et al, 2014; Kulak & Newton, 2015). Research studies on content knowledge are mixed, but PBL is generally not worse than traditional instruction (e.g. Franklin et al, 2015; Mandeville & Stoner, 2015). However, students who learn through PBL have better retention of content knowledge than students in traditional lecture courses (Dochy et al, 2003). Although not specific to PBL, a survey of research studies on the effectiveness of active learning concludes that active learning increases student achievement (i.e. results in higher grades), and, on the flip side, lecturing increases failure rates up to 55% (Freeman et al, 2014).
We have adopted this approach for the entire curriculum of our algebra-based physics course, and integrated aspects of it into the calculus-based course as well. The algebra-based course is taken primarily by general education students and students who need physics for graduate or professional school (e.g. pre-health majors). This population of students is not intrinsically interested in physics, and we have found that the problem-based approach increases their motivation to study physics. This course has been restructured so the content is presented through a series of five problem-based units. In each unit, students learn the physics content necessary to explore the problem. Each unit concludes with a project in which they apply their newfound understanding of physics.
Video Analysis
Alternative Energy
Accident Reconstruction
Bridge Design
Space Exploration
Solar Cookers
Optical Instruments
Photovoltaics
Power Generation
Biological Applications of Electrostatics
In implementing this pedagogical approach, we have learned a few lessons. First of all, the amount of content covered in an introductory physics (or any science) course is absurd. There is just way too much for the students to absorb it all. To address this issue, we have cut back on the content in our courses, while still ensuring that the most important ideas are covered. For example, we still cover Newton’s Laws, but blocks on inclined planes are out because they do not advance their understanding of a fundamental physics concept or help them to understand a particular case study.
The most challenging part of adopting this pedagogy is finding good problems. Relatively little has been published for introductory physics courses, and so we have been generating a lot of new course materials. A few references are given below, and we are hoping to publish some of our materials in the near future. If you are game to try some our lessons, send me an email and I’ll get you the materials.
Further Reading & Resources
Case Studies for Teaching Science at University of Buffalo
Problem-Based Learning at the University of Delaware
Context-Rich Problems at the University of Minnesota
Other References
Barrows, H. S. (1996). Problem-based learning in medicine and beyond: a brief overview. In L. Wilkerson, & W. H. Gijselaers (Eds.), New directions for teaching and learning, Nr.68 (pp. 3–11). San Francisco: Jossey-Bass Publishers.
Becerra-Labra, C., Gras-Marti, A., & Torregrosa, J. M. (2012). Effects of a Problem-Based Structure of Physics Contents on Conceptual Learning and the Ability to Solve Problems. International Journal of Science Education, 34(8), 1235-1253.
Dochy, F., Segers, M., Van den Bossche, P. & Gijebels, D. (2003). Effects of problem-based learning: A meta-analysis. Learning and Instruction, 13: 533-568.
Franklin, B. M., Xiang, L., Collett, J. A., Rhoads, M. K., & Osborn, J. L. (2015). Open Problem-Based Instruction Impacts Understanding of Physiological Concepts Differently in Undergraduate Students. Advances In Physiology Education, 39(4), 327-334.
Freeman, S., Eddya, S., McDonougha, M., Smith, M., Okoroafora, Jordta, H. & Wenderothah, M. P. (2014). Active learning increases student performance in science, engineering, and mathematics. Proceedings of the National Academy of Science. 111(23), 8410-8415. Accessed online at http://www.pnas.org/content/111/23/8410.full
Hilvano, N. T., Mathis, K. M., & Schauer, D. P. (2014). Collaborative Learning Utilizing Case-Based Problems. Bioscene: Journal of College Biology Teaching, 40(2), 22-30.
Kulak, V., & Newton, G. (2015). An Investigation of the Pedagogical Impact of Using Case-Based Learning in a Undergraduate Biochemistry Course. International Journal of Higher Education, 4(4), 13-24.
Mandeville, D., & Stoner, M. (2015). Research and Teaching: Assessing the Effect of Problem-Based Learning on Undergraduate Student Learning in Biomechanics. Journal of College Science Teaching, 45(1),