"Some people help keep Earth clean by picking up litter. Others plant trees to help clean the air. Look inside to find out more about helping planet Earth." -- Publisher's description.

"Where does your water come from? Water falls as rain or snow. Water collects in rivers, lakes, and oceans. Some of this water can be cleaned and used for drinking. People work to make sure Earth has enough clean water. This book will tell you how you can help"--Publisher's description.