Live From Mars was active July 1996-December 1997.
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 were impressed!
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.