The Water Cycle Page
Earth is covered with water.  Water circulates between the Earth's surface and the atmosphere.  The sun heats the water on the Earth and it evaporates (changes from a liquid to a gas).  The water vapor rises up and cools in the atmosphere.  When water cools, it condenses (changes from a gas to a liquid) into droplets. These droplets form clouds.  The droplets can fall down to the Earth as rain, sleet, snow, or hail depending on the weather conditions. 
(See diagram below)
Water Cycle Links!
Brain Pop - Fun site with  about the water cycle, solor system, human body, and more.
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