Rather than simply presenting the activity, I saw this interest as a vehicle for learning. From our observations and from non-fiction books we learned that rocks are made of minerals. We learned that rocks form in a variety of ways but the most exciting way to a PreK student is through volcanoes. So we added a science experiment by creating volcanic eruptions (reaction) with baking soda and vinegar.
And last of all, a few odds and ends from the week.