The water cycle, also known as the hydrological cycle, is the process in which water moves and changes on Earth. All the water on Earth, whether it’s the water that we drink, the water that sustains the ocean or the rain that falls from the sky, has been around for millions of years. Because of the atmosphere, water molecules are trapped here on Earth for us, and all other life forms, to drink, use and enjoy.

There are three states of water: solid (ice), liquid and gas (water vapor). Water changes from one state to another because of the application of heat.  As you heat up the molecules in ice, it melts and becomes water and eventually evaporates into water vapor. Removing that heat causes water to condense and reverse this process.  This is the water cycle.

You can easily make your own mini water cycle at home using just a few materials. Here is what you need:

• 1 plastic tub
• 1 plastic cup
• 1 small rock or marble
• 1 roll of cling wrap plastic (or similar)
• 1 roll of wide tape to seal the still
• Soil or sand
• 1 – 2  cups of water

Directions:

1. Add your soil to the plastic tub.
2. Position the plastic cup in the center of the tub, partially submerged in the soil for stability.
3. Sprinkle 1-2 cups of water over the soil.
4. Seal the tub with cling wrap and tape. Add a pebble or large marble directly above the cup forming a depression in the cling wrap.
5. Place the solar still in a still and sunny location. Observe your still throughout the day. What do you notice happening?

Follow-up Questions:

1. How does water get into the oceans?
2. What are clouds? What are clouds made of?
3. How does rain form?

Did you build your own water cycle? We want to see! Send us a picture at [email protected] and be featured on our blog.

Are you a teacher who wants to use environmental education lessons in your classroom? Checkout Project SWELL: a school-based science curriculum that teaches children about the importance of the San Diego region’s waterways. The project helps teachers empower students about how to understand and improve the condition of San Diego waterways.