Dear Teachers,

I have a couple of "hands-on" activities for your class.  We can make an astrolabe, which is used for measuring angles above the horizon to stars and planets, (and with a tape measure and a little math can be used to determine the height of buildings and trees and such).  The other is simply using a stick/pencil/crayon and their hand to tell time--the Hand Sundial.

    Here are some materials which you may download and have prepared by your children for my visit:

For the "Do-it-yourself-astrolabe"   each child will need:

   1)  a six inch diameter paper half-circle

   2) drinking straw (best if non-bendable)

   3) push-pin

   4) 6" to 8" length of string, and some clear tape

   5) some sort of counter-weight--a marker with a cap will do in a pinch   

   Using a protractor, have the children mark off ten degree intervals, or more if they wish, with Zero at the bottom of the curve, and 90 at either end, thusly:

:

 

For the Hand Sundial, all that's needed is a straight stick or pen, knowledge of north, and a sunny day. 

We can also try to sketch the moon and sun, if the numbers of children are managable.  All that's needed there would be a white page with two circles spaced apart on it.