Lillian C. McDermott
27
History
3/15/10
G.
Production of
Physics by Inquiry: A Video Resource
In the late 1990s, Joyce Evans at NSF suggested that we collaborate with WGBH
Boston to demonstrate how we work with teachers.
WGBH would create a video during
our NSF Summer Institute that could be used by faculty to prepare K-12 teachers to teach
by inquiry.
We were not eager to undertake this project because of concern about possible
negative effects on the Institute participants.
When we were assured, however, that we
would hardly notice that videotaping was taking place, we submitted a proposal to NSF.
Early in the summer of 1999, a filming crew with massive videotaping equipment
arrived.
It was impossible to ignore their presence.
It was often necessary to move in
order for the camera angle to be adjusted or for a voice to be picked up by the microphone.
In some ways, the filming was a harrowing experience, but the crew were invariably polite
and the teachers were good sports.
My colleagues and I were self-conscious about being
interviewed on film.
Everyone was relieved when the experience was over.
Peter and I
traveled to Boston to consult on the final version.
Not wanting to spend much time on
production details, we did not fuss as much as we later wished that we had on the choice
of background music or animated cartoons.
I guess our judgment was not universally
shared because
Physics by Inquiry: A Video Resource
received an
International
Association of Audio Visual Communicators (CINDY) Award Gold Medal
in 2001.
65
IV.
Research and Development:
Tutorials in Introductory Physics
Until the 1990s, the Physics Education Group had been known primarily for our
work with K-12 teachers.
Our earlier development of curriculum had been devoted to
Physics by Inquiry.
Tutorials in Introductory Physics
began a new era in our history.
66
A.
Relevance of Research to Introductory Physics Courses
During the development of
Physics by Inquiry
, we posed a number of qualitative
questions, not only to preservice and inservice teachers but also to students in the large
introductory courses.
The responses demonstrated that on certain types of non-
quantitative problems, the average performance of students in introductory courses is
65
Physics by Inquiry: A Video Resource
, Boston: WGBH Educational Foundation (2000).
66
L.C. McDermott, P.S. Shaffer, and the Physics Education Group at the University of Washington,
Tutorials in Introductory Physics
,
First Edition
(Prentice Hall, Upper Saddle River, NJ, 2002);
Instructor’s Guide
(2003).
(The
Preliminary Edition
was published in 1998.)
Lillian C. McDermott
28
History
3/15/10
often the same before and after standard instruction: irrespective of mathematical level,
whether standard demonstrations are or are not used, whether a concurrent standard
laboratory course is or is not required, in large or small classes, and regardless of the
lecturer’s popularity.
Analysis of the data indicated that the gap between teaching and
learning is much greater than most instructors realize.
(Even the 5% who statistically
might become physics majors often made errors similar to those made by other students.)
Electric Circuits
67
We began our study on student understanding of electric circuits with individual
demonstration interviews.
These were followed by written questions like the one below.
What students could
not
do
Rank the bulbs from brightest to
dimmest.
Explain.
The bulbs are identical.
The
batteries are identical and ideal.
Results independent of whether administered
before or after instruction in standard lecture courses
Correct response
given by ~ 15%
–
students in calculus-based
physics
(N > 1000)
Answer: A = D = E > B = C
A
B
C
D
E
given by ~ 70%
–
graduate TA
s and postdocs in physics (N ~ 100)
–
high school physics teachers
–
university faculty in other sciences and mathematics
Pretest on resistive electric circuits.
Three simple circuits, each containing an ideal battery and one or more identical
bulbs, are shown in a diagram.
Students are asked to rank the brightness of the bulbs.
No
calculations are necessary to determine that the two connected in parallel are equally
bright and as bright as the single bulb and that the two connected in series are equally
bright but are dimmer than the others.
This type of non-numerical question has proved
challenging.
Only about 15% of the students in standard calculus-based physics courses
have given a correct response after lecture and laboratory instruction. These results have
been independent of whether the question has been asked as a pretest (before instruction)
67
L.C. McDermott and P.S. Shaffer, “Research as a guide for curriculum development: An example from
introductory electricity, Part I: Investigation of student understanding,”
Am. J. Phys.
60
(11), 994 (1992);
P.S. Shaffer and L.C. McDermott, “Part II: Design of instructional strategies,”
ibid.,
60
(11), 1003
(1992).
See also the
Electric Circuits
module in
Physics by Inquiry
.
