We designed CGC to be pretty much self contained, so that even a missionary family in a remote location can use it without any additional resources. Most of the activities use items you have in your kitchen. For example, to explain the difference between pumice and obsidian, you would use an egg white. The egg white just sitting there represents the obsidian; it is glassy in appearance, you can see through it and it doesn’t take up much volume. Then you whip it up with an egg beater, and it now represent pumice; it is dull in appearance, you no longer can see through it, and it takes up more volume with the added air, but has no additional weight. However, you may use any resources you have available (such as textbooks, encyclopedias and so forth) to enhance the lessons. We do have some suggestions of items we particularly like, such as the Moody Science videos, listed in the “Digging Deeper” section.