Discussion of the section on light beams
We're not "finished" with light beams. The light station is a tool that produces a straight, sharp beam of light, which we will use in future activities involving reflection and refraction.  Now, here are some things to do to finish this little introduction section for light beams.  Discuss these questions with the people in your group:
  1. In these activities the viewing screen was a white screen on the table, and the slot that made the beam was vertical.   Suppose we wanted to show a light beam to a class, using a vertical viewing screen (like one of those white boards you write on with marker pens, or a piece of paper tacked to the wall), and have a horizontal beam. How would the light station need to be redesigned so that it could be used this way -- or will it work like it is? (In any case, explain how to do it).
  2. There are other ways to make light beams:
    *Laser pointers make very nice beams
    *Some flashlights make nice beams
    *We could put a bright light behind a metal shield with a small hole in it.
    There are also other ways to make them visible
    *We can clap erasers to make chalk dust
    *We can make fog of various kinds
    *We could check the position of the beam by putting a white card into it.

    No doubt you can think of some more! Discuss the advantages and disadvantages of the light station, relative to any of the others.

These discussion questions are a bit open-ended, and some people find them very confusing. We have provided some examples of good and bad discussions on a separate page.  Please send us your discussion of these two questions.  Don't forget to tell us who is in the group.
If there is something that you don't understand about light and shadows, Ask us!
This is the end of this section. Please note that these activities are written up (in slightly different form) in the manual (in the Light Beams section).
The next section is about mirrors.