Building Conceptual Understanding in Introductory Physics
Vincent P. Coletta
Completion of Project: May 10, 2005
The fundamental question was: could I improve my concept-based teaching by further development of questions, including some that are tied to filmed or simulated experiments?
My project goals were: 1) for all my students to achieve improved conceptual understanding of introductory physics; 2) for those weakest students to achieve a greatly improved conceptual understanding of introductory physics. My project objectives were: 1) even better performance by my students on the standardized exams FCI and MBT; 2) greatly improved performance on FCI by those students with the lowest scores.
My plan was to create new concept-based questions, including some that are aimed at students who would be identified as having weak scientific reasoning ability, based on their scores on Lawson's Test of Scientific Reasoning Ability. Some of the questions were to be designed to correct specific kinds of reasoning deficiencies identified by Lawson's Test. Some of the questions were to be integrated with either computer simulations or filmed experiments. The development of these questions would be based on individual work with several of the weakest students taking introductory physics from a colleague in the physics department.
I worked with four students enrolled in PHYS 101, taught by a colleague. These students all scored well below 50% on Lawson's Test, indicating very weak scientific reasoning skills. I worked primarily on developing their ability to do proportional reasoning, contrasting constant ratio problems with constant difference problems, such as age difference. I developed questions involving applications from everyday life, such as determining which size pizza is the best buy, or determining the size of objects in a photographic enlargement, given their sizes in the original photo. I developed an animated computer program for the photographic enlargement problem, in which the students are taken through a series of questions and are asked to check their answers, based on proportional reasoning, by making on-screen measurements of objects with a movable ruler. I also worked with these students on physics concept questions. I found a source of hundreds of physics simulations and wrote conceptual questions to accompany many of these simulations, in a style suitable for use in the LMU Interactive Physics Classroom, using a personal response system.
Meeting Goals and Objectives
I have had only a limited opportunity to measure the extent to which my goals and objectives were realized, in that, since the completion of the project, I have taught introductory physics only once to a very small summer school class. Three of the six students in that class had SAT scores of 1400, and their scores on Lawson's Test were also quite high. Even so, I am able to evaluate to some degree the effectiveness of this course, in which I used new conceptual questions developed in this project, compared with past courses. My analysis is based on the research data I have accumulated, which shows correlation between conceptual achievement (as measured biased gain on the Force Concept Inventory) and reasoning ability (as measured by Lawson Test scores). The summer school class average Lawson score was 79%. The best fit line for all my data indicates that past students with a 79% Lawson score had an average FCI gain of 0.45. My summer school class achieved a considerable higher average gain: 0.58. (1.0 indicates a perfect score; traditional lecture classes have gains of about 0.2). Their performance on the Mechanics Baseline Exam was also higher than for any other class I have taught.
As for the four PHYS 101 students I worked with, unfortunately their performance showed no significant improvement over what we expected to see based on their Lawson scores. Reflections
This project is a small part of a continuing effort to improve the teaching of introductory physics by both developing instructional materials and techniques, and by developing assessment tools to evaluate the effectiveness of those materials and techniques. The teaching of physics is becoming a science, and I have been very active in helping to lay the foundations of this new science. I have made my physics animation concept questions available to colleagues in the LMU physics department. Hopefully, the kind of analysis of reasoning ability that I do will be useful to faculty in other disciplines. My presentations sponsored by CTE may inspire others to use some of the techniques that I use in my classes, such as concept based multiple choice questions, peer instruction, and computerized student responses.
Since the completion of this project I have become aware of a new dimension affecting student success in physics, namely their attitudes and beliefs about the nature of learning physics. This is a promising new area to explore.
Dissemination Past and Future
In addition to two talks at LMU this fall, I recently gave talks based on my recent work at the University of Notre Dame and at the national summer meeting of the American Association of Physics Teachers. A few weeks ago I had a paper (coauthored with Jeff Phillips) accepted for publication in the American Journal of Physics. I have also recently submitted a paper (also coauthored with Jeff Phillips) for publication in The Physics Teacher. I plan to continue giving talks and writing articles based on work in this project and related projects.