Re: Test Writing

[Kossom <MKossover@NEWMANSCHOOL.ORG>]

Howdy-


From: Tina Fanetti [mailto:FanettT@QUEST.WITCC.CC.IA.US]
Sent: Tuesday, April 30, 2002 7:53 AM

> On the last test I asked students to explain the difference between a
> real and a virtual image.

With all due respect, you got bad answers because you asked a bad question.

You will be happier with questions that ask for applications of knowledge.
After all, this demonstrates an understanding of the material. I don't care
if my students memorize their notes. I want them to understand them.

A better question that gets at the difference between real and virtual
images (a topic that I avoid since I don't believe in virtual images, see
below) might ask, "Explain the difference in these two situations. (a) A
slide projector creates an image on the wall that everyone can see. Each
person is asked to draw a picture of the image. Everyone's picture looks
nearly the same. (b) A person looks through a magnifying glass at a stamp.
Another person looks over the shoulder of the first person. Each person
draws a picture of what they see. The two pictures are not the same."

----

Instead of talking about virtual/real images, I only discuss the images made
on the retina. They are always real. We look at how lenses change the angles
of the incoming rays on the lens.

Marc "Zeke" Kossover