People have said you can teach any subject at any age. Jill Paton Walsh’s The Green Book is proof of that. 

The plot centers around a group of families who leave earth to make a new home on an alien planet. The story tells virtually nothing about their life before leaving Earth or about the journey or the spaceship, but rather focuses on their struggle to survive on a world where they are unable to find edible food. Because of the limited space on the ship, each passenger can only take one book with them. (This book was written in 1982 so on one thought of ebooks yet.) The protagonist, Patty, chooses a book of blank pages with a green cover, hence the name of the story. The unique characteristic about Patty is, she is only eight years old.  

Although the language is so simple that a child can follow along, the world building is unique, and the prose allows the reader to experience the new planet in vivid detail. There is virtually no characterization of Patty or anyone else in the story. Despite Patty’s young age, however, she is the one who saves the colony by making the discovery that solves the colonist’s food problems. The purpose of bringing a book of blank pages is made clear at the end: Patty wants to record the colonist’s history on the new world.

The Green Book is a delightful story that allows young children to experience Science Fiction in the same way as older children and adults.