Re: [Phys-l] computational physics activities (was: universalgravitation ....)

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

If it is indescribable, then it does not exist.  Research at Colorado showed
that in some cases students who had virtual labs rather than physical labs
not only learned the concepts as well, but could perform faster when wiring
physical circuits.

While some experience with physical systems is probably important, physical
labs have the difficulty that they can not reveal certain details.  Virtual
labs can be setup to not only be physically realistic in the important
details, but also to show invisible details that are necessary for student
understanding.

At present there is no research which shows what students may be lacking in
understanding by doing virtual labs.  There is research that shows that
paper and pencil tasks are inferior to exploration labs using the sonic
ranger, and that video analysis of movies falls in between these methods.
Notice that the sonic ranger has made it possible to show in real time
things that before were only seen by laborious analysis.  In that respect
they are similar to virtual labs.

The BIG advantage to virtual labs is that irrelevant details that confuse
students can be filtered out.  When doing labs with the sonic ranger
students will often say that bigger ripples in the graphs are the sign that
you have higher acceleration.  This happens even when they are repeatedly
told to ignore the ripples.  Virtual labs do not have this artifact.

When it comes down to teaching, the research has already shown that many
things that people thought worked, plainly do not.  For example,
conventional demonstrations that have been the staple of physics lectures
simply DO NOT work.  But with some drastic modifications they can be made to
work.  Catherine Crouch at Harvard showed that they do not work, and
Thornton & Sokoloff have published a research based set of "Interactive
Lecture Demonstrations" that do work.  So citing a belief, or it is logical
that... is not enough.

Priscilla Laws, one of the major PER researchers, said that while her
intuition for what works has gotten better, it is still not that good, and
she always has to look at the evidence.  Robert Karplus did this when he
designed his elementary school program.  He discarded many more ideas than
he actually kept.  So please define what indescribably important is lost,
and if possible cite research which shows this.

John M. Clement
Houston, TX

> Computers can be used to advantage IN CONJUNCTION WITH real
> honest-to-goodness lab work ... but when they are used instead
> of lab work, something indescribably important is lost.