Winifred Malvin [Carver Elementary]
Investigating Snails
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]
Static Electricity
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
Boats
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:
environmental education |
clean water |
natural lands/ open space |
|
less conflict |
clean air |
racial justice and equality |
less crime |
cures for illnesses |
less trash |
enough food for all people |
healthy fish population |
bees |
fewer invasive species |
smart growth |
otters, bobcats, and eagles |
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.