Oh god, I did Odyssey of the Mind for a couple years in elementary school. At the time it was somewhat fun, but in retrospect it was pretty ridiculous.

I think I did "Crunch" (building a balsa wood structure to hold weight) and "Scientific Safari" (some really lame skit thing)...

http://www.odysseyofthemind.com/materials/1995problems.php#p...

http://www.odysseyofthemind.com/materials/1996problems.php#p...