Earthquakes and Volcanoes
The month of Geology is one of my favorite months to teach. I always start with the book HOW TO DIG A HOLE TO THE OTHER SIDE OF THE EARTH. I first explain that it is
impossible to dig through the earth. The book takes us through the layers of the earth. I use Playdough to build an earth. I use a magnet marble to act as the core. The core is silent iron and acts as to create a magnetic field in the earth. That's why a compass points north and why we have a north and south pole. The core is as hot as the surface of the sun and we pass it around and play hot potato. I then pass out pieces of yellow dough and have the kids put it around the core. This is the outer core. We placed on orange dough for the mantle (hot magma). We finished with flat pieces of brown dough to be the plates of the earth. When we finished I showed the kids where the pieces overlapped and made mountains and gaps where you can see the magma, where volcanoes form. I then cut the earth in half to show the kids the layers. I had a container of red jello which I called the magma and I floated graham crackers on top as plates. I showed them how the plates could float on this and cause earthquakes. I showed them a map of where the plate lines are and let the students see that we are in the middle of the plate and in a safe place. I had pairs of of wooden blocks with modeling clay on top. The children pulled on the blocks until the clay split causing an earthquake.
Volcanoes - I had drawings of shield, cone and strato volcanoes. I talked about the two types of lava, aa (slow, thick lava) pahohoe (fast, runny lava). We then looked a cross section of a volcano and looked at the parts. I then erupted one with baking soda, vinegar and soap. I also erupted one with ammonium dichromate. I burned it in a bottle cap on top of a volcano model. You can order the am. dichromate for around twelve dollars.