In Victor
Barocas's biomechanics class, it's almost time to take a vote. The
PowerPoint projection on the huge screen in the steeply banked auditorium
shows a rudimentary drawing of a stick that's being acted upon by the
force of gravity at its center of mass and by a rightward horizontal force
at its base.
A few accompanying lines of text summarize the problem, pose the question "What
will the stick do?," and submit a menu of possible answers:
A) Rotate clockwise.
B) Rotate counterclockwise.
C) It won't move.
D) You don't have enough information to answer the question.
Barocas, an associate
professor in the biomedical engineering department, wanders around the auditorium
casually sipping from a soft drink can while listening to the undergraduates'
small group discussions. Occasionally Barocas addresses a student by name
as he interjects a question or makes a comment that provokes a quiet laugh
or two. But now it's time to close the discussion and vote.
"Everyone who thinks the stick will rotate clockwise, raise your hand," he declares.
Proof of Barocas's efficacy as a teacher, the correct answer (B) wins by a landslide and provides a lead-in to the lesson: basic physical principles governing the motion of a patient's upper body in a motorized wheelchair.
Also vindicated is Barocas's deceptively casual instructional style. What seems like an impromptu and unscripted class diversion is actually a carefully thought-out teaching moment.
"I probably take a poll once a week," he says. "It may be my favorite way
to introduce a new topic. If I just asked the question, ?no one would respond.
But the poll requires only a show of hands, doesn't make a student look dumb
by being wrong in front of the entire class, and lets the student know that
she or he is not the only person in the room who doesn't get it. I find this
quite effective."
For Barocas (ChemE Ph.D. '96), who joined the University faculty in 2000, the key to good teaching is a "student-centered approach"?\organizing the learning experience in ways that give students confidence in their ability to learn.
"If I can get them to believe in themselves and in the class, they will work harder and pay more attention, and then they will learn," he says.
His students tend to agree. Biomedical engineering junior Santhi Elayaperumal says, "A student in Barocas's class is more likely to perform better?\because of his interaction with the students. When there is any sort of personal connection between teacher and students, the students almost always will try to excel in the class."
Barocas tries to shape the classroom experience in ways that maximize opportunities for the sort of personal connections that Elayaperumal admires. He seeks to bridge the sometimes intimidating intellectual distance between student and professor.
"I try to engage the students in nonthreatening ways," he says. "[One] technique is to give the class a fairly simple problem to do and then walk around the class while they do it. The advantage [is] that I speak to individuals, and I find they are much more willing to talk to me about their poor understanding [of the material] one-on-one without having to make the effort to come to my office."
Humor also helps. "I make a lot more jokes in my lecture than most people," he says. "My theory is that if everyone [else] in the room laughs, the kid who isn't paying attention might wonder what's so funny and then start listening to me for a few minutes."
