Re: position vs displacement

[Hugh Logan <hloganPHY@CFL.RR.COM>]

John Clement wrote:

> > Pedagogical remark:  The idea of relativity of position is obvious
> > to us.  It's not a big surprise or a burden on students, but it
> > needs to be discussed explicitly.  It gets short shrift in a lot
> > of texts.
>
> Actually relativity in position is often a big surprise to students, and
> when discussed explicitly they often will still not understand it.  This is
> true especially of students with thinking skills below the formal
> operational level.  It requires a lot more than mere talking at them about
> it.
Many years ago, I saw a newspaper article that stated that elementary
school children were being taught
relativity. I think they were referring to Robert Karplus's SCIS program
for elementary science, which was based on Piaget's cognitive theory and
learning cycles. The relativity  was most likely relativity  of
position. I recall  that SCIS utilized a polar coordinate frame to be
made on a plywood platform. It might have disappointed parents expecting
their children to be budding Einsteins, but it might have helped
students with thinking skills below the formal operational level that
John refers to.

Hugh Logan

PS  I did not see the previous messages in this thread when I submitted
my most recent message.