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

Announcements:

Section A: [K-5]

Barbara Lorde (Attucks School) Exploring Triangles, Rectangles, Circles, and Squares
She has been teaching for a long time, and has a third grader to type up her lessons for her.  Her purpose was to introduce shapes and make designs. She cut down on some of the activity by cutting out the shapes herself.  We formed groups to arrange patterns on paper.  One group made a rectangle, measured its length and width with a ruler, and computed its area using the relation (third grade activity on Math Skills)

Area = Length ´ Width

Leticia Rodriguez (Peck School, First Grade)
provided a variety of activities relating to volcanoes, including a video of Magic Sound Bus Blows Its Top.  She showed a Volcano Kit, which makes a correspondence between volcano parts [lava, magma, ring of fire] with parts of a boiled egg [yolk, egg white, shell].  This was a very rich presentation of information and visualization on the environment, which introduced big words and made them easy to understand.  She gave us instructions on making a volcano from scratch, and presented it as a scientific experiment with hypothesis, data, and conclusions to employ the scientific method.

She showed us the invisible Ring of Fire on the Globe.  See the websites

She also discussed illustrating the concept of potential energy at the first grade level with a slingshot and a rubber band eraser.

Jean Essig (Woods School, Kindergarten) Air Science Tricks
made a Hot Air Snake, and caused it to spin and spin and spin.  She invited us to make our own snakes from colored paper. More than ten of us were soon showing how our snakes moved up and down like spiral springs.  She also suggested several extensions:

Mamie Hill (Woods School)
used dried peas and toothpicks that had been soaked overnight to make all kinds of figures, including three dimensional figures.  Soaking provides flexibility and softness that greatly simplifies the construction of figures. When the peas dry overnight the figures become stable.

Beverly Merchant (Soujourne of Truth School)
made colorful and sparkling shapes out of pipe cleaners using an Epsom Salt [Magnesium Sulfate] solution. She put a shaped pipe cleaner into the saturated solution, and the salt crystallized out along the pipe cleaner. People were given their cups of solution and pretty colored pipe cleaners, for making their own shapes and showing them next time.

Notes taken by Earl Zwicker and Bob Foote 

Section B: [4-8]

Roy Coleman, Lee Slick, and Kerri Kerfin (Morgan Park HS)  How to React to An Experiment
led a measurement of reaction time (to check to see if you are still alive).

The idea is for one person to drop a meter stick held vertically, with its bottom at the top of the fingers of (partially opened) hand of another person, which is resting on a table top. The first person drops the meter stick, and the second catches it as quickly as possible.  The meter stick typically falls a distance s of 20 - 30 cm, corresponding to a total reaction time (t) determined from the formula s = 1/2 g t2 ;  or s [cm] = 490  t[sec]

s (cm) t (sec)
11.0 0.15
19.6 0.20
30.6 0.25
44.1 0.30
This reaction time is the sum of three separate times:
Reaction Time = Brain Processing Time + Nerve Transmission Time + Finger Closing Time

They estimated the first time by setting up two funnels attached with rubber tubing and held from behind at the ears of a participant.  When the tubing was tapped, the participant was able to hear which ear heard the sound first and louder, unless it was tapped within s = 5 - 10 cm of the middle of the tubing.  Thus, the Brain Processing Time is given as s / Vsound = 0.0003 sec.   The finger closing time is estimated by seeing how quickly the fingers can be opened and closed [about 30 times in 10 seconds, corresponding to a closing time of 0.167 sec.] They then conclude that most of the time is associated with the Finger Closing Time, and that the Nerve Transmission Speed is comparable to the velocity of sound, or about 300 meters/sec.

Comments by Porter Johnson:  The nerve transmission speed is certainly not larger than the speed of sound, and most estimates indicate that it is considerably smaller.  Check these references:  

Beth Womack (Gunsaulus School) Bridge Design (Project-Based Learning)
provided the groups with a supply of the following materials:  Clay, Craft Sticks, Tape, and Newspaper, and presented us with the following questions:

  1. Getting Started
  2. Design Description
  3. Conclusion
We constructed several types of bridges in the various groups.  Three made tower bridges out of sticks and clay, one made a tube bridge out of newspaper and clay, one made a popsicle-clay span, and one made a pontoon bridge.

Barbara Pawela (retired) Seeing the Invisible

Notes taken by Porter Johnson