Bridging Concepts and Skills: Tim Shedd's take on structuring lecture courses
Tim Shedd, professor of Mechanical Engineering, believes that the movement towards teaching conceptual understanding is necessary and important, but one that must be tempered by reinforcing problem-solving skills. "It's more important for students to learn that F=MA and what that really means than to be able to calculate the acceleration of a baseball," Shedd says, but "in engineering classes, there are also a lot of necessary skills... You have to be getting those skills across. You do have to know how to calculate the acceleration of a baseball."
Shedd worries that without careful planning, classes focusing primarily on conceptual understanding can devolve into students' memorizing the answers to conceptual questions without probing into their underlying meaning, just as they might previously have memorized equations. In both cases, Shedd feels that students miss out on the kind of flexible knowledge necessary to approach real-world situations.
To answer this difficult classroom problem, Shedd has attempted a hybrid approach to lecturing, structuring his class around weekly concepts, but teaching each topic in a way that makes the real-world applications clear and demands students' development of several kinds of problem-solving skills. One of the main changes comes out of a new text by ME colleagues Prof. Greg Nellis and Prof. Sanford Klein: problems that use computer-based methods to examine real-world issues.
"I'm trying to do projects, [based on] really complex problems that I wouldn't have given two or three years ago," Shedd says. "These are numerical problems - extensive homework problems - but they're based on projects that I might have done as a consultant or in my research... That's the key thing in this class [Elementary Heat Transfer], all of the assignments are very realistic. They're not typical textbook problems."
Shedd has organized each week of class around a topic, and each class around a different aspect of the necessary conceptual understanding. For example, on Mondays, he introduces the topic of that week's class, on Wednesdays he does an example problem, implementing the concept through a simple analytical example done by hand in class. Finally, on Fridays, he introduces the complexities of computer modeling, looking at the problem by examining situations where it would be necessary to get an exact answer.
"I want to use the lecture time to emphasize problem solving, and how to approach complex problems, as well as how the solution method connects to concepts," Shedd says. "Before, students would complain to me that I would focus too much on concepts and not examples... Students would always ask for examples, but there never seemed to be enough time to cover both the important concepts and examples of the problem solving skills. Now, since the book has such good examples, as well as a very good presentation of the concepts, I can focus more on problem solving skills. My hope is that the lectures will become quite interactive, so that I can answer questions about concepts that come up in reading and the homework assignments, as well as the lecture material."
The homework problems mirror the lecture structure: First students analyze the problem conceptually, then set up a solution by hand, and finally use a computer to implement the problem, get an exact answer, and interpret the results.
Shedd acknowledges that this method of teaching does have some drawbacks: for one thing, its success depends on students' independent reading and preparation to understand (and hopefully contribute to) the problem solving. Another challenge, he says, is that the success of this method "depends on good week-long homework assignments," which can take a significant amount of time to write, tune to students' ability level, and grade.
"What I'm trying to do is to get the class to be very interactive, so I want the homework problems to be hard, and I want the students to be thinking. I want them in my office hours every day, that's where the learning occurs."
Overall, Shedd believes that this method is beneficial for students - "much more interesting than going through the book" - and good for their conceptual understanding, both of the course's subject and how it applies to real-world situations. "They like the fact that they feel it's applicable" to their future careers, Shedd reports. "I'm trying to use the lecture time in a better way. This is the area of my research and my consulting, and so I can bring in experience and tell them that this is material that [they're] going to use."
Shedd's students concur with this assessment. As one student says, "[The assignments aren't just random book problems that someone threw together at the last minute... They're well thought out and they make us use concepts that [were] taught us in class... [they] make us pretend we are engineers... and I liked that aspect of the problems a lot."
For more information about the ideas in this article:
1) Martin, J.K. & Mitchell, J.W. (2005). Experiences Combining Technology, Assessment, and Feedback to Improve Student Learning in Mechanical Engineering Thermal Science Courses. Paper presented at the ASEE/IEEE Frontiers in Education Conference, Indianapolis, IN. [Available online through the FIE 2005 conference proceedings search.]
Martin & Mitchell describe a system of techniques for combining technology and assessment in undergraduate lectures on mechanical engineering. The techniques described here are different from Shedd's, but maintain a focus on conceptual knowledge and engineering skills, and as such provide a complementary case study.
2) Miller, R., Streveler, R., Olds, B., Chi, M., Nelson, M., & Geist, M. (2006). Miconceptions about rate processes: Preliminary evidence for the importance of emergent conceptual schemas in thermal and transport sciences. Paper presented at the ASEE/IEEE Frontiers in Education Conference, Chicago, IL. [Available online through the ASEE conference proceedings search.]
and Streveler, R., Geist, M., Ammerman, R., Sulzbach, C., Miller, R., Olds, B., & Nelson, M. (2006). Identifying and investigating difficult concepts in engineering mechanics and electric circuits. Paper presented at the ASEE/IEEE Frontiers in Education Conference, Chicago, IL. [Available online through the ASEE conference proceedings search.]
These papers make a strong case for teaching concepts by identifying common student misperceptions about such topics as engineering mechanics, electric circuits, fluid mechanics, and thermodynamics. Both papers identify some of these misconceptions and attempt to uncover and understand the mental models that lead to these misconceptions.