Teacher, Charlie Lindgren describes
I apologize for this being so long, but it's a story that must be told.
I am in the middle of Activity 2.2 (pages 34-35) of the Teacher's Guide
and want to give you a progress report. I have had two of the greatest days
with this lesson!!! This is the end of my igneous unit. So far we looked
at igneous minerals and then at the rocks they formed. Then we looked at
the two major types of volcanoes (shield and explosive) and discussed the
reasons why they occur. As a part of this we watched last year's Nova "Hawaii,
Born of Fire" (excellent flick!!!) which led us to becoming "Planetary Geologists."
Working on Activity 2.2
Yesterday we created the cinder cones using different varieties of sand.
I used a VERY coarse sand (Sanabel Island Shell/sand), small mineral chips,
coarse aquarium sand, VERY fine Caribbean white, and Hawaiian Black with
the curse removed. In addition to measuring the angle of the slope I also
had the kids measure the height and find the circumference by drawing
a line around the outside of the cinder cone. Then they poured the sand
back into the beaker and either measured the diameter with a ruler or
simply counted the lines on the graph paper. I had them pour the sand
onto graph paper that had each centimeter accented with 0.2 divisions
in between. In addition to doing this we digitally photographed "the best"
cone of each type from the top and side with a Connectrix(?) 8 bit black
and white camera and saved to disk. The kids loved it!!
Today we discussed the angles and why so many people came up with so
many different slopes. We had a great discussion of error! Then I asked
them what they thought the steepest slope they could comfortably walk
up would be (remember this?). They all fell into the same trap we did
saying 35 to 70 degrees (I teach 8th grade). Then I broke out the 2 X
10 plank and ladder and we tested our ability to measure angles. With
one person doing the walking, two spotting and one holding the ladder,
everything went smoothly. (Many people looked askance at me for trying
this. I told the principal and warned the nurse in advance.)
Now for the neat part! After it was over, I photographed the ladder/plank
at its maximum slope and put the pict file into the NIH program, and we
measured the angle using the software. It was incredible! The maximum
angle was only 32 degrees! They thought for sure it was going to be 65
or 70! We then went back and did the same thing with the photos taken
the day before of the various slopes, heights, and circumferences. In
one class ALL of the slopes came out within 2 degrees of one another!
Because they had done the activity on graph paper, we had a ready scale
to calibrate the software to measure the circumference and height. They
This lesson was one of the best examples of integrating technology into
a science lesson that I have ever seen. Thank you Passport to Knowledge
for giving me the initial idea.