Walk When the Moon Is Full is about two real children, Alan and Elva, who called their father Hammy and their mother Fran. They lived on a 240-acre farm in Wisconsin and longed to go exploring at night. Elva, the younger, liked to climb trees. Animals trusted her to come very close and her keen ears heard the faintest sounds. Alan had a small but sensitive nose that found and remembered smells, just as his mind remembered facts. He liked to find things out. Fran promised the children that she would explore with them twelve times every month when the moon was full for a whole year. Then Alan laughed. The moon is full thirteen times a year. Hammy and Alan laughed because Fran didn t even know the moon is full every 28 days. Each time they walked in the moonlight they found something new; sometimes they found animals eating, playing, or fighting. Once Hammy took the whole family to the city and they were surprised at what they found there, too. This book has thirteen surprises.