"Do you like to ride a bike? Bike riders use energy from their bodies to power their bikes. They don't use up other kinds of energy. Why is it important to save Earth's energy? Find out inside. Then learn how you can help"--Publisher's description.
"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.
"Do you walk to school? That's just one thing you can do to reduce pollution and help keep our world clean/ Look inside to learn more about what you can do to keep Earth clean"--Publisher's description.