In the fourth Mysterious You book, Zzz ?, kids uncover the secrets of sleep to find out how the body clock works, why the brain needs sleep, what happens during REM (Rapid Eye Movement) sleep and more. This unique book explores the mysteries of the human body using a mix of thoroughly researched factual information, amazing anecdotes and surprising try-it activities. Did you know? * If a person lives to be 70, they'll have spent 23 years sleeping. * Wolfgang Amadeus Mozart was inspired by music he heard in his dreams. * Gorillas who've learned sign language have been known to sign in their sleep!
