The Teaching Exchange: Technology and Challenge-Based Learning

This article was originally published in the Fall 2002 issue of the CFT’s newsletter, Teaching Forum.

by Derek Bruff

In this column, we highlight innovations in teaching across the campus. In this issue, we interview two Vanderbilt faculty members associated with the VaNTH Engineering Research Center. The VaNTH ERC is a center organized by the bioengineering and learning sciences faculties of Vanderbilt University, Northwestern University, the University of Texas at Austin, and the Health Science and Technology Program of Harvard and MIT to perform research on bioengineering educational technologies. For more information on the VaNTH ERC, visit the organization’s Web site .

Duco Jansen is an assistant professor in the Department of Biomedical Engineering in the School of Engineering. He currently teaches a freshman seminar on laser vision correction and a senior-level course on biomedical optics.

In what ways has your association with VaNTH impacted your teaching?

The exposure to the learning sciences people involved in VaNTH has really changed the way I teach. As a graduate student working in an engineering environment, I was not exposed to a variety of teaching strategies. The idea of students learning in a problem-based setting rather than in a classical lecture setting has changed my philosophy of teaching. Now instead of lecturing on how light moves around tissue, I might pose a relevant medical problem and ask my students, “How can we solve this?” The students brainstorm their initial thoughts, and then they research the problem by listening to experts, reading papers, or following a lecture. Then they come back to the same problem, and I ask, “What do you think of it now?” There’s still a place for lectures. I’m not saying we should get away from that entirely. Rather, the “time for telling” happens in the context of a real problem.

What kinds of technology do you use in your classes?

One tool that lends itself well to this exploratory process is the Personal Response System (PRS). It’s a bit like the “ask the audience” portion of “Who Wants to be a Millionaire?” in the classroom. I pose a multiple-choice question, and each student answers using a wireless device. Those signals are sent to the computer in the front of the classroom, and a bar diagram is displayed showing the distribution of answers. The students find out whether or not they have the right answer, and I find out whether or not the students are grasping the concept. The system allows me to be a lot more focused in my lectures. I don’t have to spend time with something everybody already understands. When half the class answers incorrectly, I know to go back and say, “Wait a minute. There’s something missing here. I have to go back to that.” It’s a much more targeted approach to teaching, and I think a much more efficient use of time. It certainly engages the students.

The limitation of the PRS is that it’s a passive interaction. Students pick A, B, C, or D, rather than generating their own thoughts. There’s a project called the VaNTH Student Assessment System that was designed to overcome this limitation. It’s the PRS with the ability to ask short answer and essay questions in addition to multiple-choice questions. The input devices are the laptops that the School of Engineering now requires all of its freshmen to purchase.

In what ways do your students engaged in learning?

Here’s one example of how I’ve used this system. I’m teaching a freshman engineering course on laser vision correction. On the second day of the course, I brought in ten cow eyes. We’re studying laser vision correction, so the students should know what’s in the eye. At the end of class, after the students dissected the cow eyes and identified all the structures, I asked them to list sequentially the structures light has to pass through in order to get to the back of the eye before an image can be formed. Rather than choosing a sequence from a choice of possible sequences, the students had to actively generate a sequence and they had to know the terminology themselves. That’s a good example of the more interactive, generative approach that you can use.

Stacy Klein is an adjunct assistant professor in the Department of Biomedical Engineering in the School of Engineering. She currently teaches a freshman seminar on electrocardiograms at Vanderbilt. She also teaches math, physics, and biomedical physics at the University School of Nashville.

In what ways has your association with VaNTH impacted your teaching?

I particularly value the challenge-based form of teaching I’ve learned from VaNTH. It gives a purpose to the learning. The students have a challenge. I just actually finished this challenge with my physics class: “Your grandmother has had a recent right hip injury. In which hand should she put the cane and why?” It focuses our entire topic. I like that we can always refer back to the challenge. There’s always a reason for what we’re doing in class. They’re not doing it just because I told them to do it, but because they’re worried about poor grandma. I also like challenge-based teaching because it begins with a question, but then it immediately follows that by having the students generate their own ideas, telling me where they’re coming from and what they already know. Sometimes they tell me things that are either wrong or not relevant, but it’s fun to watch them figure out that their ideas were wrong or not relevant. I think they take more ownership of it that way. They get more excited about it. We’ll spend several weeks on that one question, and it’s fun because they keep bringing up grandma in class. I find it much more motivating and much more interesting to teach that way. It’s definitely changed how I run my classroom.

What kinds of technology do you use in your classes?

In both the biomedical physics class I teach at the University School and the freshman seminar I teach at Vanderbilt, the students analyze their own electrocardiograms. Here at Vanderbilt we use something called LabJack to hook up the students to my computer and take their ECG data. At the high school level, we use Texas Instruments graphing calculators since all of our students own those already. We have a number of Calculator Based Laboratories that allow students to connect their calculators to different sensors, including an ECG sensor. The students are responsible for recording their own ECGs three times and then going through a mathematical analysis to see how normal they are.

I have a module on medical imaging in my biomedical physics class, and the radiology department has given me a long-term loan of an ultrasound machine. Near the end of the module, I take a large turkey and insert pimento-stuffed olives in the turkey to act as tumors. The students use the ultrasound machine to do a needle biopsy in class, detecting the location of the olives and extracting a piece of material from each olive. They totally get into it, acting like doctors. It’s kind of humorous, but they get a lot out of it. It’s a fun grand finale for the unit.

In what ways do your students engage in learning?

What fun is it to study electrocardiograms if you can’t take your own? I think it makes the class much more hands-on. Rather than looking at a computer where somebody gives you a data set, or worse yet, hearing me talk about it, they actually take their own data and analyze it themselves. It makes it much more real. It gives the kinesthetic learners a chance to do, feel, touch, see. It adds a whole new dimension to learning that needs to be there.

The Learning Sciences thrust of the VaNTH ERC provides much of the foundation for the curriculum and learning technology development done by the organization, including work done on the challenge-based learning method mentioned by Professors Jansen and Klein. A key component of the Learning Sciences thrust is the How People Learn framework, which synthesizes research on human learning and how to enhance and assess it. For more information on the Learning Sciences thrust of the VaNTH ERC, visit the thrust’s Web site .