What Makes a Children's Book Great? We Have Some Answers from the first children's book conference run by Scholastic and Publishing Perspectives
A great book is...
1. One that contains a simple and original idea presented with clarity and great power.
2. One that connects with the reader, asserting its world directly into the reader's mind.
3. One that makes the world seem larger and more interesting.
4. One written with humor and a light touch.
5. One that is a realization of a complete but very different world.