Please excuse the cross post, but there are now 2 debates on the same topic
about both topics.
Some of the arguments that have appeared in PHYSLRNR and PHYS-L have echoed
some things I said a while back. At the present moment physics is currently
taught first under the name physical science or IPC (integrated physics and
chemistry). Sometimes this consists of 75% or more chemistry with some
physics sprinkled in. However even when it is taught as 50% physics,
students do not really learn much. They memorize and regurgitate facts
which are not remembered for more than 2 weeks. They leave with essentially
their misconceptions (preconceptions?) untouched. The same thing happens in
chemistry courses. Students leave them still believing that matter contains
molecules rather than understanding that matter is made up of molecules.
The only bright spot that I can see is the physical science pedagogy being
promoted by the Modelers. They are now spreading the idea to the 9th grade
and finally instructors are using Clement&Camp "Preconceptions in
Mechanics".
Changing the pedagogy to enhance learning is supposed to be solved by
training teachers better. The problem of getting different departments
together at the university level is a well known difficulty. Beyond that
most professionals in physical science and math. departments do not endorse
or use inquiry learning. Many think that didactic methods are the only ones
that work, and they will not cooperate in such an endeavor. In the physics
community many do not accept FCI/FMCE results and do not accept that the
Hake survey shows that dramatic improvements in education can be made. As a
result prospective teachers are only exposed to inquiry by reading about it
in education texts and they are not equipped to implement it.
Assuming that it is possible at some universities to have a truce in the
turf wars and implement inquiry training, another mine field awaits. Once
teachers have been taught by inquiry methods, they then have to implement
them in the classroom. This is just as big a leap. Schools often oppose
it. Conventional textbooks are mandated, and some schools mandate that
every teacher in a subject has to be on the same page on the same day. This
is now becoming prevalent in TX districts. Mentor teachers oppose it and
force the trainees to use conventional didactic methods.
This also does not take into account the high stakes testing which forces
teachers to teach a scattergun approach so that all topics are covered.
Frequently principals will mandate constant review exercises which are
didactic in nature.
At this time the early science courses are extremely controlled by the state
standards, but physics as an elective is not. It is possible in many
schools for physics teachers to implement inquiry methods. This would argue
that physics last can be a better deal.
Beyond the institutional barriers are the cognitive barriers. According to
Piagetian theory students acquire the ability to do "formal operational"
reasoning around age 12, but before that they can only perform at the
concrete operational level. In reality only a small fraction acquire this
ability at that age. With time the fraction rises, but by the end of HS it
is only 20% and at the end of college it is only 30% according to some
surveys. Shayer&Adey point out in "Really Raising Standards" that delaying
physics to the senior year takes advantage of the increase in thinking
ability. This factor has never been considered by those who advocate
physics first.
Biology is actually a good match for students who are concrete operational.
It contains many descriptive concepts which are easily grasped. The
research that shows this has been done by Anton Lawson at AZ State in a
series of remarkable papers in Jour. of Res. in Sci. Teaching. He has shown
that concrete operational thinkers can easily grasp descriptive concepts,
have more difficulty with concepts that involve change over geological
times, and have the most difficulty with theoretical concepts. Theoretical
concepts are concepts are things that are not directly observable.
According to his classification almost every physics concept is theoretical.
Chemistry has more theoretical concepts than biology, but fewer than
physics, so it is a good next step.
The advantages of physics first are all based on the idea that physics is
necessary for chemistry, which is necessary for understanding biology. In
reality many practicing chemists do not understand physics very well, and
biologists often understand it even less. While the advantage of the
physics, chem, biology sequence is logical, there is to my knowledge no
evidence to show that it produces superior results.
On the other hand, a good grounding in physical science concepts may be
achievable without specifically being labeled physics. But to improve
student understanding of such concepts it may be necessary to improve the
level of student scientific thinking. This means attacking the problem of
middle school and 9th grade physical science. Fortunately there is an
existing program which is being used successfully in England. It is
"Thinking Science" by Shayer, Adey & Yates. Its specific goal is to raise
student thinking ability in middle school, and it succeeds admirably. The
previous reference to Shayer& Adey is an excellent guide to this and other
programs. For a short reference see Philip Adey's monograph at Innodata http://www.ibe.unesco.org/International/databanks/Innodata/inograph.htm .
This particular program has some very large advantages that make it
possible.
1. It does not change the current curriculum
2. It only requires 70min every 2 weeks.
3. It has a well defined training program that works.
4. It uses simple inexpensive materials.
The real advantage of this program is that as teachers learn to use it, they
become attuned to inquiry teaching. Over time they change the existing
curriculum to be more inquiry oriented. This produces and even bigger
effect. Essentially while raising student abilities it upgrades the teacher
abilities. The main disadvantage is that it requires training, and that
training is currently available only through Kings College. They have kept
the program on track by controlling the training.
Along with the 9th grade Modeling program, these are probably the best
available programs.
As to the elementary teacher problem, the same difficulty exists. According
to Arons in "Teaching Introductory Physics" the large proportion of
elementary teachers are concrete operational. Such individuals will have
difficulty in implementing inquiry lessons. However he also points out that
85% can be raised to the formal operational level. Currently as far as I
know this problem is not being attacked at any level with a notable
exception. Biology courses at AZ State have been constructed so that the
thinking level rises dramatically during the course. If this could be done
in college biology, surely it could also be implemented in HS biology.
While I do not think that physics first is viable for the various reasons I
have cited, I might agree that it is a reasonable thought. Unfortunately I
know what will probably happen if physics is universally taught in the 9th
grade rather than in the 12th in the near future. It will tend to be taught
by recycled physical science teachers and the current pool of good physics
HS teachers will dry up. This would mean even less understanding of
physics, and make the current problems even worse. Along with this would
probably be a push for more rigorous 9th grade science which is a code word
for more memorizable facts.
I would say that physics for all or rather physical sciences for all is the
goal to push for rather than physics first, provided it can be done with
research based inquiry teaching.
John M. Clement
Houston, TX
This posting is the position of the writer, not that of SUNY-BSC, NAU or the AAPT.