Your body goes through a cycle of five different stages when you sleep. The fifth stage is known as Rapid Eye Movement (REM) sleep. Learn about the fascinating ways the human body functions in How I Sleep, a My Body title. Each title in the series introduces readers to the ways in which their body senses things, grows, and interacts with the world around them. My Body is a series of AV2 media enhanced books. A unique book code printed on page 2 unlocks multimedia content. These books come alive with video, audio, weblinks, slideshows, activities, hands-on experiments, and much more. Follow these steps to access your AV2 book.

Step 1 Find the code on page 2 of this book. Step 2 Enter the code at www.av2book.com. Step 3 Explore the AV2 media enhanced book. Book jacket.