Kids, if anything, are harder to write for because they are a more discerning audience. They will not stay with you if you go off on a tangent or if you give them extraneous information that doesn't serve the story. You really have to tell a tight story. You have to give them humor and suspense and believable characters. All those things that adults want too, but you have to be really on your game when you're writing for kids.
Rick RiordanSelling one's book to Hollywood is rather like selling someone your house. After it's sold, it isn't yours anymore. They can paint it a different color, tear it down and build something new, or do anything they want.
Rick Riordan