Book excerpt: Click flashlights, light lanterns, and get ready to turn electric lights out to celebrate Earth Hour! Wherever you are, you can help our planet. Kids around the world use electric energy to do all kinds of things--adults do, too! From cleaning the clothes we play in, to lighting up our dinner tables, to keeping us warm and toasty when the weather is cold, electricity is a huge part of our lives. Unfortunately, it can also have a big impact on our planet. Earth Hour--a worldwide movement in support of energy conservation and sustainability--takes place each March and is sponsored by the World Wildlife Fund for Nature (WWF). During Earth Hour, individuals, communities, and businesses in more than 7,000 cities turn off nonessential electric lights for one hour. Across each continent--from the Eiffel Tower to the Great Wall of China to the Statue of Liberty--one small act reminds all of us of our enormous impact on planet Earth.