Chronology Current Month Current Thread Current Date
[Year List] [Month List (current year)] [Date Index] [Thread Index] [Thread Prev] [Thread Next] [Date Prev] [Date Next]

Re: Physics for Ninth Graders?



At 18:16 -0500 9/25/01, Kossom wrote:

Many people keep saying that physics can be taught at a much more advanced
level to seniors than to freshman.

Well, to quote a freshman, "DUH!"

The problem is that all the sciences can be taught at a higher level to
seniors than to fresman.

I have been saying for years that physics can be taught earlier than
the 12th grade, and it should be. But just dumping into the nith
grade isn't the solution either. The basic problem is that our
pre-high school science education is a joke. The kids essentially do
busy work for the time they are supposed to learn science and really
get nothing from it. We need to examine the European "spiral"
approach to see how it ought to be done. It isn't that we have to
"dumb down" physics so that it can be taught as a terminal course to
ninth graders; we need to teach the early concepts to kids starting
as early as they can be expected to grasp them. This should begin
with probably the fourth or fifth grade, and should be carefully
structured to those concepts that they can grasp at each level. We
could start with, say, the idea of convervation of volume for solid
materials, uniform speed, the idea that things fall because of the
presence of the earth. Get them thinking about why the earth is
round--they all know it by then, but they couldn't tell you how we
know that. They need to start learning to ask the question "How do we
know that?" and they need to start learning some of the volcabulary
of science. They can also start learning how to draw a graph, and how
to collect things--how to choose what fits into a desired category,
how to decide on categories, in other words, how to look
systematically at the world. As time goes on, these concepts are
revisited each year, but each time at a slightly higher level,
conservation of volume becomes density, which then delves into
liquids and gases, Then into things that intermesh with each other,
so suddenly volume is not conserved, and so forth. Constant speed
becomes constant velocity, then realtive velocity, then add uniform
acceleration (I'm not necessarily advocating this in particular, it
is a suggestion about the progression), and so forth. Each topic
becomes a bit more complex with each return, and new topics can be
inserted as the students become ready for them.

In this way, we can expect that the students will be able to do
certain things when they get to the ninth grade, and even more by the
time they get to the twelfth grade. But we have put them on a ramp to
understanding and not a cliff. Keeping the cliff but just making it
lower because the kids are starting in the ninth grade is no
improvement.

John Denker pointed out that my characterization of conservation as
understood by beginning students as "turn out the lights" was the
same as minimize the use of Gibbs free energy. OK, do you want to try
to teach the concept of Gibbs Free Energy to students who are still
struggling with the basic concept of energy? This is what Chemistry
teachers do every year. At least those who get their students before
they get to physics.

I'm not at all sure that the scheme of biology, chemistry, physics,
in that order, has been as much of a success as Michael Edmiston
thinks. If it has, then why does such a low percentage of HS students
take physics at all? I think we can do it better, but it involves
much more than just reversing the oreer of presentation. It involves
a major rethinking of the philosophy of science education in the
pre-high school years.

Hugh
--

Hugh Haskell
<mailto://haskell@ncssm.edu>
<mailto://hhaskell@mindspring.com>

(919) 467-7610

Let's face it. People use a Mac because they want to, Windows because they
have to..
******************************************************