Below are instructions for a volcano cake that really "erupts"
Make your favorite chocolate cake recipe and bake in three 6 inch round pans and one 8 inch round pan
Cut the top off of a small empty water bottle. Cut a whole in the center of the 6 inch cakes to fit the bottle.
Stack the 6 inch cakes around the bottle spreading chocolate frosting between layers
Frost the 8 inch cake with white frosting.
Using a knife cut the 6 inch cakes around the bottle to the shape of a volcano and frost with chocolate frosting
Place the volcano on the center of the 8 inch cake
Sprinkle graham cracker crumbs on the white frosting of the 8 inch cake
Decorate the cake with green frosting for the greenery, blue frosting for the water around the base of the cake. Add trees and dinosaur molded out of fondant (optional)
Place a small piece of dry ice in the bottle. Add warm water and watch your volcano erupt