Elementary Mathematics-Science SMILE Meeting
06 February 2001
Notes Prepared by Porter Johnson

Section A: [K-5]

Monica Seelman (Williams / St James School)
gave us a handout entitled Super Spinner, and from the many bags she had set out on the table, she began to pull out one example after another of tops.  Holding one up, she explained how she had made it by cutting a disk from stiff paper.  She had placed a pencil through its center and used some tape to keep the pencil fixed.  She had taped 5 pennies equally spaced about 3/4 radius from the center.  She gave it a good twist with her fingers and set it spinning on the table.  And she explained that her students could explore how the number of pennies and their placement might influence the top's behavior.

She showed and spun a variety of tops she had made from a variety of plastic lids, and used pencils through their centers as axes.  How to find the center of the lid?  Trace the circular outline of the lid on a piece of paper, and cut out the circle.  Then fold the paper circle into quarters; the intersection of the fold lines is at the center.  Place on the lid and you have the center located to make a hope for the pencil-axis.  Neat!

Use toothpicks for spin axes for smaller tops.  Dreidels [ traditional Hanukkah presents] make good tops [see the website http://www.marshmallowpeeps.org/tops/dreidels.html and http://www.holidays.net/chanukah/dreidel.html], and open the dialogue for discussion of different cultures [ http://www.ohr.org.il/special/chanukah/chan95.htm].  

She gave us a plastic bag handout for us to use in groups of three or four, to make tops and spin them.  Each bag contained a pencil, pennies, a lid, push pin, and two rubber bands.  

We sure had fun with that.

And finally, she showed us a commercial Tippi Top.  When set to spinning on its bottom, it would turn over by itself and spin on its stem.  Why?

Rae Lynn Schneider (Williams School)
gave a presentation entitled Flow-and-Go Boat, which used gravity to power a boat that would go with the flow.  Two Styrofoam™ plates were glued together, rim to rim.  Then the rim of a Styrofoam™ bowl was glued to the center of one of the plates.  A hole was poked through the side of the cup near the bottom.  A straw was pushed through the hold, short elbow first, and the hole was sealed with glue.  The bottom of the cup was glued to the center of the bowl, and it was allowed to dry overnight.  Then she set the boat at the end of a clear plastic box containing water, with the straw underwater.  She filled the cup with water.  the boat moved forward.  She put a drop of food coloring in the water to show the trail of water.

Christine Scott (Beethoven School)
did a presentation using different food products to investigate changing solids into liquids.  First, peanut butter was made by grinding peanuts with a blender.  We also put various different fruits in a blender, liquefied them, and added juices.  In another activity we made butter.

Marjorie Fields (Young School)
used laminated red and green paper apples to have us discover all possible combinations for a pre-determined total.  The leaves were numbered 2-18.  These are the totals involved.  The students use dry erasers to write an addition fact for the number on each apple.  The student then writes all combinations to get that total.

Erma Lee (Williams School)
had the class to do a fun project on body parts.  She had parts of the body pictured on paper circles.  She also had the skeleton parts of the body on different paper circles.  The students matched the exterior body part with the skeleton part that was underneath it.  Little pieces of candy shaped like body bones were used then put together to make a skeleton.  [Were these  pieces left over from Monster's Night??]

Notes taken by Earl Zwicker and Barbara Pawela

Section B: [4-8]

Therese Donatello (St Edwards School / Science)
lead an exercise on Reaction Time (The time it takes the brain to react to a stimulus).
Problem: You are to develop and write procedures to answer the following questions:

  1. How fast do you react?
  2. How does your reaction time compare to others in the class?
  3. does your reaction time become shorter with practice?
  4. does your writing hand respond faster than your non-writing hand?
Materials: A penny and a meter stick.
  1. Write procedures that will answer each question in the problem using the materials given.
  2. Make data tables to record your findings.
  3. Carry out the procedures after groups have formed, and record your data.
  4. Discuss results and draw conclusions.
Two of the three groups used the meter stick alone [although one group thoughtfully suggested that the penny be used to buy bubble gum to relax the participant], and reaction time was measured by seeing how far down the meter stick it could be caught, when dropped while suspended with its bottom at the location of the person's hand. They proposed measuring the distance d fallen by the meter stick, and using that as a gauge of reaction time. One group felt that you should calculate reaction time directly, using the formula
d = 1/2 g t2
or d [cm] = 490 {t (sec)2
d (cm) t (sec)
4.9 0.10
11.3 0.15
19.6 0.20
30.6 0.25
44.1 0.30
The third group knocked the penny off the meter stick in a controlled way, and then counted how long it took a person to catch it in air.

Chris Etapa (Gunsaulus Academy)
had us construct a Universal Sundial using the following materials:

The idea is to develop a set of instructions that are so clear and straightforward that children can read them and make the sundials---at present, at least, the kids can do it with a little help! This sundial is "universal", in the sense that it provides accurate results at any time of the day, and at any latitude, in the Northern Hemisphere, at least. The project is being developed at the Museum of Science and Industry, and a preliminary version of these instructions appears under the Exhibits section, under Time: http://www.msichicago.org/scrapbook/scrapbook_exhibits/time/educ_pages/act_univ_sundial.html.  Porter Johnson mentioned that these sundials are "universal" only in the Northern Hemisphere, because in the Southern Hemisphere the sun lies in the Northern part of the sky, and the shadow line should move from West to East as the day progresses.  For details see the website http://www.sundials.co.uk/faq.htm.

Porter Johnson (IIT)
made a simple demonstration of electrostatics from 3 Styrofoam™ coffee cups, a toothpick, and a small quantity of water.  He took the toothpick and poked a small hole in the bottom of the first cup, and left the toothpick sticking in the hole.  Then he put water into that cup, and held it up to show that the water dripped through the hole and into the second cup, which was held below the first one.  He rubbed the third cup across his clothing or his hair, in order to produce a static charge.  He then held the third cup close to the dripping water, and the drops were deflected toward the third cup because of the static charge.  He explained that the neutral water droplets would be deflected toward the cup, whether it had a positive or negative charge, because the induced polarization charge would result in a net attraction.

Notes taken by Porter Johnson