He showed us the balancing nails trick (which they have at Explora in Albuquerque, too).
There was a flexagon with drawings of stages of evolution. In this video (linked from his site, to YouTube) he shows a food chain. Any four-part series could be illustrated on those, he said. (He told us who discovered/created this design first, too, but I don't remember the name, so if anyone does know, please leave a note.
Pictures of the building in which he and his team work, and some of the things we saw: