Rocks are Fun

We've continued with our study of rocks this week and have another fun experiment to show you.

My last post about our rock unit talked about how we learned about minerals and rocks using gumdrops to show how the molecular structure of the two differ. By the way, the mineral at the end of that posting was ice. Another highlight this week included a food-based experiment explaining the difference between sedimentary, metamorphic, and igneous rocks. First, we layered sugar, crushed graham crackers, chocolate chips, and marshmellows in a ziplock bag. This represented sediment. I explained that if this harded, it would become sedimentary rock.

Then we were to apply pressure in the form of a rolling pin and heat in the form of sunlight to the sediment. The pressure wasn't difficult. Here's a photo of the kids in action.

And since it was snowing outside, as Mika is demonstrating, the heat part was trickier. I substituted 5 second bursts in the microwave. What we ended up with respresented metamorphic rock. Then, we dumped our metamorphic rocks into a saucepan and applied high heat to turn it into magma. After that, we cooled it in the fridge. The resulting "rock" was igneous rock. It was an interesting experiment and showed how you can have different types of rock using the same materials. The kids even ate some of their igneous rocks.

I got this experiment from Experiments with Rocks and Minerals by Salvatore Tocci.

We are growing a salt crystal garden and alum crystals right now and will post photos of our results when they are done.