Why are Dr. Seuss books so good?

Dr. Suess books are written in a different style from traditional books.  They are written with a play on words, have made up words that are tongue twisters, and use carefully crafted silly rhyming and poetry to make the reading fun.  Some of the most famous Dr. Seuss books are Green Eggs and Ham, Cat in in the Hat, and How the Grinch Stole Christmas.  An example of the poetry and rhyming from a Dr Seuss book is "one fish, two fish, red fish, blue fish" and "look at me, look at me, look at me now, its fun to have fun, but you have to know how."