This has always been one of my favorite books by Dr.Seuss and recently bought it for my 4 year old son. He is really interested in the book and it is great how there is no happy ending, the future depends on us to clean up. After reading the book, we were watching animal planet and they were talking about how these rare breed of monkey are loosing their habitat because of logging in Malaysia and my son said, "that is just like in the Lorax mommy, we shouldn't cut down so many trees and make the monkeys go away should we?" I was so impressed that he was able to apply what he had read from a children's book to what he saw on a program.