Science Experiment: Erupting Volcano

This year for science we are doing Earth Science. I picked a curriculum that was a little above my 2nd graders level and a little below my 8th graders level so that we could work together. Two days a week we do science together. Day one we learn about a topic like say 'Earthquakes' and Day three we do an experiment pertaining to the subject. Days two, four and five my older son does extended work: more reading, research and writing.

This past week the topic was Volcanoes. Our experiment was of course to build and erupt a volcano. I'll be honest with you; I've never actual done one of these before. I never had to do one in school and as science was my least favorite subject in school, I had no desire to build one of these in my free time. So armed with instructions and intuition, we went to work on it. The good thing is that my oldest son loves science and building. So I mixed up some homemade play-doh and let the boys put it together over a small water bottle. I then assisted in the mixing of the ingredients to bring about the eruption (outside of course). We had a great time! And I think we might do it again sometime.

Recipe for homemade Play-doh:

Mix 6 cups of flour, 2 cups of salt, 4 tablespoons of cooking oil, and 2 cups of water in a large bowl. This will make a volcano the size of ours as we used ALL the dough. If you want something larger you will have to double or triple the recipe.

Instructions to build an erupting Volcano:

small drink bottle
60 ml water
1 tablespoon baking soda
1/4 cup vinegar
orange or red food coloring
few drops of detergent

After building your volcano, let it sit overnight to harden. You can also use clay or other material of choice. We built ours on a cookie sheet covered in wax paper. That made it easy to transport around as well as clean up. I advise you to do the eruption outside--just in case. Place water, soap, food coloring and vinegar into the drink bottle. Last you add the baking soda. The instructions we worked off of said to wrap the baking soda in tissue paper and then drop it into the bottle as the last step. I like this idea as it gives you a minute more to see the eruption take place. My advice would be to make sure the tissue paper is super thin to fit into the bottle. Then your volcano will erupt. Make sure to have your camera and video camera at the ready. Also, you can paint your volcano or decorate it to make it look like a real volcano with a city down below to be destroyed. Make it as fun as you like. We plan to make several adjustments when we repeat this experiment at some point in the future.