If you are into the math behind origami, Eric M. Andersen's origami page
paperfolding.com has a very detailed and concise explanation of the geometry involved in origami and it's potential uses, such as in an educational setting. This site also provides examples (and diagrams) of intermediate origami of dinosaurs, insects, and animals such as Collin Weber's
Frog on a Lily Pad shown below. Each project includes a picture of the completed origami as well as step-by-step diagrams. The diagrams are a bit complicated and sometimes difficult to read but provide a useful guide to intermediate origami artists.
