This blog follows the adventures of a former engineering professor bringing hands-on engineering and science activities into a local elementary school. Follow along with me, check out the activities I use, how they work, and the excitement of the kids as they begin to develop or deepen their love of engineering and science.
Wednesday, April 13, 2011
Weathering and Erosion, Part 2
After more experimentation, I am going to finish showing photos of the experiments that we are going to run for Friday.
I tried the marble experiment again, but in reverse this time. Actually, freezing marbles overnight and carrying them to school packed in ice is much easier than boiling them at school and then freezing them. I took some marbles and froze them for an hour or so. I then took a coffee cup and boiled water in the microwave, which is something that I have easy access to in the school. I took a cold marble and dropped it in the cup and then, POP! The marble gave a nice little pop, and I poured out the water and marble and had a fractured marble.
I will do this experiment as a demonstration only, and I will wear eye protection. You should not pass the pieces of marble around as they have sharp edges and could easily cut a child.
The last station I will set up will be one that discusses water erosion. I will fill a couple of tubs with dirt, and a couple with small grass hill. The children will be given small watering cans.
As you can see, as you pour the water, as expected the dirt runs down the hill. The bottom shows how much runoff there is on the hills. With enough water you will see gullys form around the rocks that are shoved into the dirt.
In the tub with the grass, you can see there is still some runoff, but that runoff is from the bottom of the hill that is not covered by the grass. I think I will experiment to see if I can tightly pack the grass hill to prevent so much runoff.
So, these are the stations that we have setup. I will be happy to send the writeup if you are interested. Just contact me through this blog.