You can build one of these things in a weekend for about $100, maybe less. They are crude, rugged, pretty light, and easy to transport. Kids love to paddle them. Almost impossible to capsize--my daughter routinely stands in hers, and dives off. And almost any age kid can help with the building. A great way to get 'em hooked--for the "real" boats that follow.

--S

Original Pop Mech article from the 60s or something: http://www.scribd.com/doc/2531554/Folding-Kayak
Duckworks improved internet version: http://www.duckworksmagazine.com/00/DM1999/articles/foldingkayak/index.htm

Another photo: http://i42.photobucket.com/albums/e315/sfitzgerrell/COLLEENWRIGHTS023lorez.jpg