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Peer Review, Winter 2005
Because Wisdom Can't Be Told:
Using Case Studies to Teach Science
By Clyde Freeman Herreid, distinguished teaching
professor in the biological sciences department and
academic director of the University Honors Program,
University at Buffalo-The State University of New York,
and director, National Center for Case Study Teaching
in Science |
Who doesn't like a good story?
Teachers and parsons have used them to perk up their students
and parishioners from time immemorial. Stories capture our
attention, entertain us, stir our emotions, and expand our
visions. Preachers use them for moral persuasion, comedians
to tickle our funny bone, and teachers as exemplars of good
practice.
The formal use of stories, called case
studies, was introduced into Harvard University's law
and business schools around a hundred years ago. Professor
Charles I. Gragg extolled the virtues of the method sixty
years ago in an article with an eye-catching title (to which
this article's title pays homage), "Because Wisdom
Can't Be Told." The title itself emphasizes the
truism that simply lecturing students about a subject hardly
ensures that they will remember anything at all. The medical
profession has known this for a long time. They have always
used case studies to instruct their interns and residents
with "war stories," but the whole process wasn't
formalized until thirty years ago, when McMaster University
introduced the storytelling method, Problem Based Learning
(PBL), into their medical school curriculum. Today case-based
teaching has gone well beyond these graduate programs, especially
in science and engineering.
Two groups are arguably responsible for
most of the excitement: the University of Delaware and the
University at Buffalo-The State University at New York (SUNY).
Both institutions have been the grateful recipients of generous
grant support from the U.S. Department of Education, the Pew
Charitable Trusts, and the National Science Foundation (NSF)
for the past decade. The University of Delaware has enthusiastically
promulgated the PBL approach across the country and urged
its adoption in every undergraduate discipline on campus.
We at the University at Buffalo have
been less eclectic. Mindful of the surveys that claim that
most U.S. citizens are scientifically illiterate and that
there is a disastrous loss of student interest in science
throughout the secondary and college years, we have focused
our attention on these problems. And we personally know some
shocking statistics about introductory science classrooms
at large universities. It is not uncommon for 30 to 40 percent
of the students to receive Fs, Ds, or withdraw. This statistic
seems to be true regardless of the skill of the instructor.
Not surprisingly, attendance in these courses is also terrible.
Even fine lecturers often end up with less than 50 percent
of their class present. Can this situation be completely the
result of the immaturity of the students, their lack of motivation,
or the fact that many of them work long hours outside of the
classroom? Is none of it our fault? Many faculty seem to act
as if it is beyond their control. But is that true?
I am especially fond of the sentences
uttered by the Swiss developmental psychologist Jean Piaget:
"At one time every teacher ought to have been an animal
trainer. When the animal doesn't do the trick, you don't
blame the animal. You blame the trainer." And change
the method of training, of course.
Changing the Training
There are lots of ideas about how to
change the training. Most of them involve active learning--getting
students to do something rather than passively receiving
wisdom. Our approach at the University at Buffalo has been
to capitalize on the inherent interest that is sparked by
stories. Not stories simply for entertainment but "stories
with an educational message." Of course, the stories can be
told in a number of different ways: through lectures (such
as when I give a lecture in the first person as Charles Darwin);
as a written story, video, or movie with a discussion following--
the method treasured by business and law schools; as a PBL
problem, which can be presented to small groups of students;
or even through one-on-one discussion, with a professor sitting
on one end of the log and the student on the other. All these
case-study approaches are important alternatives to the standard
lecture. And we vigorously proselytize all who will listen.
We have a national Web site supported by NSF where several
hundred cases and teaching notes are posted (http://ublib.buffalo.edu/libraries/projects/
cases/case.html). We hold workshops and conferences and
distribute cases in publications such as the Journal of
College Science Teaching, which runs a regular column
and has an annual issue completely devoted to cases across
all fields of science.
Teaching with cases rather than lectures
places different sorts of demands on both teachers and students.
When you give up significant control of the classroom and
actually let the students talk, who knows how the conversation
will turn out? And how will you grade the students? Such questions
can make anyone anxious. It is understandable if faculty approach
the new methodology with some trepidation and skepticism.
So, it is important to highlight some of the things that we
have learned about this new approach:
- The story of a good case study should be based upon real
events, have engaging characters, include dialogue, be short,
and have relevance to the students' lives. And it
should be a "dilemma case," which means it involves
decisions that must be made by the characters and students.
Ideally we want a case that engages students in the same
way that a detective story does. One that mimics the kind
of critical thinking that all scientists must do. Scientists
often must reach tentative conclusions on the basis of incomplete
information and then be willing to modify those conclusions
as more data become available.
- Case method teaching causes attendance to soar. Even in
large classes, attendance has approached 100 percent in
our experience with this method.
- Students' positive attitudes toward the subject
matter increases. Most students report they love learning
the material in context, something that the lecture method
seldom accomplishes.
- Most students enjoy working in teams, but it is important
to establish clear guidelines to ensure there are equal
contributions from all students.
- The instructor cannot usually cover the same amount of
material as in a lecture, but students retain what is covered
better. The lecture method produces students who seem to
forget material almost immediately after the final exam.
Students who have been taught using cases perform just as
well on standardized exams as students who are instructed
by the lecture method, but they perform much better on essay
exams where higher-level thinking skills are required.
Survival of the Fittest?
Most students indicate that they prefer
learning with the case study method; nonetheless, about 15
percent of students still favor the lecture method, even when
they have had a positive experience with cases. And those
students are in good company--after all, most readers of this
article are survivors of the lecture method and may never
have experienced anything else in the science classroom. It
is a Darwinian educational system that we have produced. Most
students do not survive the process of learning science, therefore
they go on to other fields. However, even in the face of mounting
evidence of its ineffectiveness for masses of students, we
survivors of the lecture method are reluctant to abandon our
old friend. We seem to be the exception--ones to whom Wisdom
Can Be Told. But we are few in number, and we have a
much greater obligation than to our limited numbers. Transforming
the science classroom is not beyond the faculty's control.
Through the use of PBL techniques, such as teaching with case
studies, we can engage students, provide them with the means
to learn how science works, and help them recognize the relevance
of science to society.
This work was developed with support
from the National Science Foundation. Any opinions, findings,
and conclusions or recommendations expressed in this material
are those of the author and do not necessarily reflect the
views of the National Science Foundation.
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