Date: Sun, 19 Sep 2004 16:11:54 -0500

Author: Stan Dodds

Subject: Re: Student Response Systems


As Brad and others have noted, we do this every year, probably because
there is a certain amount of pressure to show that we are 'doing
something' about teaching. Nevertheless, I think there are usable
response systems and they can add a certain amount to a physics

We have had a PRS system from EduCue (The company was recently
purchased by someone else.) for about 5 years. It is employed in both
of our big (160 students/lecture) freshman lecture courses, one
intended for premeds and the other for physical scientists and
engineers. The system is typically used by putting up a multiple choice
question tied to the immediately preceding lecture topic or a demo, and
asking the students to vote on the best answer. The lecturer then works
off the responses and often polls again after giving the students time
to argue among themselves. There might be 3-4 such cycles embedded in
an otherwise conventional 50 minute lecture. Since the remotes are not
registered to individual students we are not coercing class attendance,
using it for grading, or charging the students for use. The advantage
over paper quizzes is that it gives the lecturer rapid feedback without
the necessity of doing very much work or handling any paper

On the technical side, the hardware and software work well in this
simple application. We have had one or two remotes fail, out of 185
used for five years, and those were replaced free. Receivers have been
fine, and one major software upgrade went smoothly. The only glitches
have been caused by our IT people: They insist on periodically wiping
and reloading the classroom computers, and don't always replace our
software despite promises to do so.

Urs raises the question of whether or not there are any gains from
using lectures modified for student response in any form. The idea
seems to have started with Eric Mazur at Harvard, and he certainly
remains a proponent. He and others have published a number of papers
purporting to show real gains from their approach, but I find the
methodology dubious. It is always hard to measure psychological
quantities like 'learning' and 'satisfaction' and I don't think
physicists have any special talents for that type of measurement. The
local, non-scientific, consensus is that we didn't do any harm, in that
performance on our very traditional tests has not suffered. Student
comments, again only anecdotal, indicate that most like being more
active in lecture and that answering the occasional question keeps them
more attentive and involved. These results are certainly plausible, if
not proven. A more definite outcome is a big improvement on the
university-mandated student attitude surveys. That result, however, is
confounded by a lot of other changes that were made at the time the PRS
system was introduced. (Most notably, the courses are now taught by
young, non-tenure-track, lecturers who intend a career in teaching
elsewhere.) We intend to keep the PRS system, and the young lecturers,
but certainly can't justify it on the basis of improved learning.

Use of a response system in lectures should not be conflated with the
approach apparently adopted at MIT. From the web reference that
triggered the current discussion, TEAL is probably more akin to the
'studio physics' started by Priscilla Laws at Dickinson College and
further developed by Thornton at Oregon and by Redish at Maryland. As I
understand it, they all replace lectures by closely guided group work
involving some straight presentation from a workbook or teacher and
some concurrent lab exercises which are essentially small-scale demos.
Again, the proponents claim great results for their drastic changes,
but it is hard to know if their measures are valid. We haven't pursued
this approach at Rice because it looks too expensive in faculty labor,
space usage and student time. As others noted, it does not seem a good
environment for learning lab skills, so any such course would need to
be supplemented with a more rigorous lab period.

Thanks for listening.


From Sun Sep 19 20:55:40 2004