Make a volcano that erupts and oozes
Earth / Mud & Sand,
Red and yellow food coloring (optional)
Washing up liquid
Take small polystyrene drinking cup and cut it in half about half way up.
Turn the who cup upside down, the flip the bottom bit of the of the cup (whichi is now at the top) over and place it inside the top bit (which is now at the bottom)
This creates a handy little pot at the top in a nice sturdy stand.
Add two spoonfuls of baking soda
Add about a spoonful of washing up liquid
Add about 5 drops each of the red and yellow food coloring
Now for the eruption!:
Add about an ounce of the vinegar into the container and watch what your volcano come alive.