Did you know that the water we use today is the same water found on Earth millions of years ago? The Earth constantly uses and recycles water in a process called the water cycle. In this lesson, learners explore the four phases of the water cycle. In the investigation Rain in a Jar, learners use hot water and ice to create condensation and a tiny cloud. In Making a Terrarium, learners create an ecosystem and water cycle by growing plants in a closed environment. Investigation spans several days.