Re: [Phys-L] Conceptual Physics Course

["John Clement" <clement@hal-pc.org>]

However Newton's concept is still valid.  Algebra can give you answers
without your having to understand it.  And I pointed out that others
including UMPERG and Modeling have found that getting students to do
calculations using geometrice interpretations not only allow them to solve
more difficult problems, but also promote more understanding.  Incidentally
the authority in the snippet I provided was taken from Newton's own
statements.

So using graphs for problem solving before algebra is beneficial.  In a
concept based course, it can be used to introduce math ideas without the
students knowing it.  They don't think of graphical interpretation as math,
even though it certainly is math.  The idea that algebra is overemphasized
is not nonsense.  Students tend to just hunt for equations and rely on
algebra rather than thinking through the problem.  So making them not use
algebra, or defer it is a very good pedagogical strategy.

There is a huge misonception that having taken algebra means that students
can use it.  We all know this is not true.  The problem is that they don't
understand it, and were merely trained to do mindless manipulations that can
be done faster in a cheap calculator.  Actually once they learn the
graphical interpretations, they can easily write the necessary equations,
something the usual algebra course never teaches.  Also the graphical
interpretations are introducing calculus without the name!

Students have to be able to think proportionally before they can understand
algebra.  Only 25% of students in algebra based physics have that skill, and
I am certain the percentage is much lower in the conceptual course.

You may not like what Newton said, but it turns out he was insightful there.
It is in line with a lot of articles in JRST which show that students have
to learn to handle all 4 representations of physics.  Algebra is just one of
them, and the graphical interpretation is another equally as powerful form
of math.  If you don't like my appear to Newton read your way through JRST
and see what is needed to teach physics.  You can start in the 1970s.  If
you don't have the time to do the basic research in all fields you have to
resort to authority.  The research is there in JRST, TPT, and AJP plus other
journals.

So de-emphasizing algebra is not physics minus if you use graphical
representations.  And don't forget that the conceptual students will NEVER
use algebra after they leave school.  But they can use higher level thinking
such as proportional reasoning.  Algebra courses have failed to teach them
proportional reasoning.  Indeed I have a post and Lawson pre test for
students taking a higher level algebra course and there was zero gain in
thinking, while I did see gain in students who took the same math, along
with my physics course.  Since then I have managed to get even larger gains
in my courses.

You have to start with where the students are, and not where you want them
to be.  If you do the latter, they will memorize and never understand.

John M. Clement
Houston, TX


> -----Original Message-----
> From: phys-l-bounces@mail.phys-l.org 
> [mailto:phys-l-bounces@mail.phys-l.org] On Behalf Of John Denker
> Sent: Monday, May 14, 2012 2:13 PM
> To: Phys-L@Phys-L.org
> Subject: [Norton AntiSpam]Re: [Phys-L] Conceptual Physics Course
>
> On 05/14/2012 08:13 AM, curtis osterhoudt wrote:
> > Your statement about Newton distrusting algebra for various reasons
> > intrigues me. Do you have a source for that statement?
>
> Any such statement is at least two jumps removed from making
> sense.
>
> I don't care whether it is well-sourced or not, because this 
> is exactly the sort of thing that gives "appeal to authority" 
> a bad name.
>
> > It doesn't accord with most that I've read about or by him.
...
> HOWEVER, to use this as a pretext for trying to do physics without algebra
is nonsense.  Taking an argument for "algebra plus" and turning it into
"algebra minus" is utterly perverse.