I found this site to be a fairly good resource. Although it did not contain the information I was looking for, it did provide me with a number of links to other websites that had information on the topic I was searching.
This website is wonderful, and sometimes I find myself using the Puzzle Maker they have to make silly crosswords for my friends and family to solve. I know it sounds lame, but on a boring day you'd be surprised how fun they are! The site is very appropriate for kids of all ages, young and old alike. I don't think adults would like it (obviously, it is Discovery KIDS) but kids 7 and up should enjoy the different activities it has to offer.