Winifred Malvin [Carver Elementary]
Winifred passed around a handout Investigating Land Snails, which was recently developed by Gordon R Will, Science Consultant, Chicago Teacher's Center, Northeastern Illinois University. She applied some of the ideas in the handout, which related to the behavior of "land snails", whereas she used "water snails". Winnie placed one snail in each of 6 plastic dishes, which contained about 100 mL of water, along with a small patch of lettuce. We added a small amount of crushed ice [20 mL, say] to stimulate the snails into motion. However, we were unable to get these snails to "wake up", so that we were unable to perform experiments with them. [Perhaps we should contact a snail personal trainer.] The idea was to determine the strength of the snails, by seeing how much weight they could pull [determined directly in "paper clip" mass units, which are easily convertible into grams]. Interesting topic, good ideas --- nice shot, Winifred!
Barbara Lorde [Attucks Elementary]
Barbara passed around information from the websites Humans and Sparks [The Cause, Stopping the Pain, and "Electric People"] http://www.amasci.com/emotor/zapped.html, and Your Admirer is a Balloon! http://www.mos.org/sln/toe/admirer.html. We carried out an exercise, Salty Sounds of Static, concerning the creation of static electricity by friction, as well as attraction through static electricity. She gave us small inflated balloons, and passed around a salt shaker. We sprinkled a little salt on our desks, and then rubbed the balloons briskly about on our heads, arms, clothing, etc. --- doing whatever was necessary to generate some static electricity. We then brought the charged balloons near the salt, but not touching the salt. We found that the balloon attracted a little salt, and studied whether "more rubs of the balloon" led to "more salt", etc. We also studied "Styrofoam® attraction", as described in the website What Will a Charged Balloon Attract?; http://www.mos.org/sln/toe/balloon.html, and found that Styrofoam® leaps onto the balloon, and then jumps off after a few minutes, as explained there. You shocked us with your knowledge, Barbara!
Wanda Pitts [Douglas Elementary] Soap
Wanda passed around the handouts A Remarkable Race, as well as Scientific Method: Good Clean Fun from the book How to Do Science Experiments With Children: Grades 1-3 by Joan Bentley, Linda Hobbs [Evan-Moor Educational Publishers 1994] ISBN: 1-5579-93378. Wanda convinced us that soapy water has less surface tension than ordinary water, by having us build a "soap boat", and seeing it "shoot" across the water. We made the boat by cutting a small triangle out of a a piece of corrugated cardboard, then putting a small notch on the triangle base. We then put the boat flat on the surface of water in a bowl, with the notch near the edge. We carefully placed a drop of dishwashing liquid in the water where the notch was located, and saw the boat speed across the water! The molecules of the dishwashing fluid are attracted to water, and the dishwashing liquid breaks the surface tension, causing a ripple effect that pushes the boat forward. As an additional illustration, we sprinkled pepper over the surface of a bowl of water. When we added a drop of dishwashing liquid, the pepper moved away from the center and toward the edge of the bowl of water. For more details see the Nerdscience.com website [Be the rocket scientist you always wanted to be!], called Soap Boats - The Science of Surface Tension, http://www.ed.gov/pubs/parents/Science/soap.html as well as the presentation by John Scavo in the Math-Physics SMILE meeting of February 1, 2000: mp020100.htm. Very dramatic and exciting, and educational as well. Good show, Wanda!
Brenda Daniel [Fuller Elementary]
The Future World of Biodiversity
Brenda gave her very first SMILE miniteach presentation [welcome aboard, Brenda!!] by having us fill in a "pyramid" concerning biodiversity issues, putting the most important issue at the top, less important issues on the second row, still less important issues on the third row, and least important issues on the fourth and bottom row. The issues were take from the following list:
for all people
||fewer invasive species
Erma Lee [Williams Elementary]
The Bouncing Buttons and Raisins
Erma passed around a handout Bouncing Buttons, obtained from Junior Science Experiments on File™, published in ©Facts On File, Inc. The idea is to mix vinegar (an acid) with baking soda (a base) to produce carbon dioxide (a gas), which appears as bubbles in the glass. These bubbles will attach to objects at the bottom of the glass, and may make them light enough to float, or "bounce" off the bottom. We tried this with buttons, and found that some buttons "bounced" better than others. One can also do the same experiment with raisins. We felt that the differences were due to the following factors:
What do you think?
Very uplifting, Erma!
Notes taken by Ben Stark.