Picture books for 3- to 6-year-olds can be either fiction or nonfiction. They include both text and illustrations and generally have 32 pages and are up to 600 words long. "Cricket" magazine's guidelines for this age group require up to 800 words for fiction and 400 words for nonfiction. Poetry can be up 20 lines long.
Easy reader books for ages 5 to 9 generally have up to 2,000 words
and are 32 to 64 pages long. They can be either fiction or
nonfiction; fiction books should contain action and dialogue and
usually illustrations. They can have just a few words
per page or they can have lengthy chapters.
Young adult books are appropriate for ages 12 and up. They average 150 to 300 pages and between 40,000 and 90,000 words, depending on the target age. The books often feature characters in high school with conflicts that reflect issues typical for that age group.