Grabmonsters Rippa and Snappy are ready to get you started in disappearance calculus, the simplest math in the world. You can review them here in HTML format (shorter download time). These are full editions, but without covers, for non-commercial use without fee. You may pass them on to friends and students. In return, however, do not not alter them in any way, nor remove reference to their source.

Level 1      Who is the Foo? a Grabmonsters Mystery     HTML ebook

Level 2.1   The Grabmonsters Find Some Valuables     HTML ebook

Level 2.2   Grabmonsters Out of the Box     HTML ebook

Level 5      Grabmonsters Build a Trap     HTML ebook