The Adventures of Jonathan Gullible - A Free Market Odyssey
by Ken Schoolland
...is hands down thee best book for anyone over the age of 10. Kids young and old will love this adventure story loaded with easy to understand lessons in free market economics. I repeat, this book is NOT for kids only.
Everything else is 2nd to Jonathan Gullible.
"Capitalism for Kids" by Karl Hess is a fairly good read. So is "Whatever Happened to Penny Candy?" by Richard J. Maybury. Both are good economic books for teens and young adults