High School Biology-Chemistry SMILE Meeting
18 November 2003
Notes Prepared by Porter Johnson

Carol Giles [Collins HS] INTERNET EXPERIENCE
Carol provided us with simulated internet research projects by dividing us up in triads, giving each group several "information sheets" on a specific topic she had obtained from surfing the net. She asked us to prepare an overhead transparency that one of the group members would present to all of us. The following topics were considered:

Airbags -- pro and con.
Why do we need librarians?
What are electrolytes?
Stem Cells.
We're better off without computers.

We all enjoyed the discussions which followed the presentations and got a better understanding of what our students go through when using the internet to prepare reports. Thanks, Carol for such an insightful experience!

Christine Scott [Beethoven School] FIVE SENSES -- FLOATING AND SINKING
Christine led us through a miniteach on the senses (focussed on vision) using the optical illusion phenomenon that occurs when a drawing of two objects about two inches apart are brought toward your eyes. FOLLOW-UP SUGGESTION: Try different separation distances (larger and smaller) and also note if there are peripheral images in each case.

We then had fun with floating and sinking. Well, we didn't actually either float or sink, but observed various objects doing so:

Cans containing diet soda float, whereas cans containing sugared soft drinks sink.
An unpeeled orange floats, whereas a peeled orange sinks.
A ball of clay sinks, but it can be made to float by inserting enough straw. It works best if the clay is flattened and the straws retain air. In addition, a boat-shaped ball of clay will float.

A nice phenomenological demonstration of density, an important property of all forms of matter. That was so much fun, I'm surprised no one jumped into the dishpan! Thanks Christine!.

Ed Scanlon [Morgan Park HS] KEPLER'S THIRD LAW
Ed then led us through an activity to illustrate KEPLER'S THIRD LAW, which relates the orbital revolution time ("years") of the planets to their distances from the sun. He passed out homemade devices consisting of a medium sized rubber stopper tied to high-test fish line (100 pound), the line passed through a six inch length of glass tubing (taped on the outside for safety and to provide a firmer grip) with a washer on the other end to keep the line from sliding out of the tube. Ed then asked us to work in groups, one person wrapping the "washer" end of the line around the rod, holding firmly and swinging the stopper horizontally. we measured the revolution time as a function of the radius of the circle, varied by adjusting the string which was marked at 10 cm intervals. We all observed that the longer the string (larger the orbit) the slower revolutions (longer year) in accordance with the behavior of the planets in our solar system. We tried (not very successfully) to get the quantitative relations predicted by Kepler's third law -- perhaps some refinements to the experiment might produce better results.

Great, Ed - your usual creative approach!!

Notes taken by Ken Schug