Humor is the oxygen of children's literature. There's a lot of competition for children's time, but even kids who hate to read want to read a funny book.
The books we enjoy as children stay with us forever -- they have a special impact. Paragraph after paragraph and page after page, the author must deliver his or her best work.
I remember as a child of eight being told by a young friend that I had killed Christ. That was news to me. It's a common experience for the Jewish young. Should later generations of Germans be burdened with the guilt arising from the profound inhumanity of their ancestors? Revenge may be sweet, but guilt is non-transferable. Still, hatreds survive with the persistence of cockroaches.
Give weather reports. It helps the reality of a scene if foghorns are blowing or kites are in the sky on a windy afternoon or the day's so hot wallpaper is peeling off the walls.