I have a 12 year old son with learning difficulties, I recently had a Volcano to do for my son's Scout project, we always have creative projects to do. Paper mache is excellent (which is thin strips of newspaper), you get a balloon and add the paper mache on with glue or paste, you wait for the Paper Machet to dry and then you pop the balloon, you can then cut this into a cave or make it into land. You can get rolled up card or loo rolls and crepe paper to make the trees, or with paper machet. Cereal boxes or any cardboard boxes are good to use as a base and then poster paints can be used to paint.