I like the idea of using either a cording or pin tuck method for the tucks. For info on how to do a cording or pin tuck, go to http://thelacedangel.blogsp...
If you need a super simple volcano recipe, it doesn't get much easier than this. Prep is about 3 minutes, and there is no clean up necessary. Easy Baking Soda and Vinegar Volcano Eruption for Kids by Preschool Inspirations