Have you seen the Horrible Science series?

Every now and then while browsing the library book sale cart we hit on a golden find, and last weekend was one of those times.  We found 7 books in the "Horrible Science" series by Nick Arnold.  I linked one of them above.  I'm telling you both boys are simply loving these books, reading and running to me telling me gross pieces of information.  The books are chapter books basically but have cartoons, quizzes, case history types of things, diagrams, etc., so reading level is easy for Noah even, but Zach is interested in the information as well.  They are really well done to fit the elementary ages, more interesting than say the Usborne encyclopedias (those are a bit dry for Noah at times though great pictures), but still packed with info. 

Here is the author's site as well for anyone interested in some extra fun: 
http://www.nickarnold-website.com/index.htm#