We will spend about one-third of our lives sleeping. Sleep affects every aspect of life, including learning, memory, mood, and behavior. This engrossing book teaches readers about the sleep cycle and circadian rhythm. The effects and consequences of sleep deprivation are detailed, as well as common sleep disorders such as insomnia, sleep apnea, delayed sleep phase syndrome, restless legs syndrome, and narcolepsy. Diagnosis, treatment, and steps that teens can take to improve their sleep are also covered in this accessible and illuminating volume.