The Water Cycle � Science for Kids
The water cycle is the process by which water circulates through the world. This cycle begins with the sun, which heats bodies of water such as rivers, lakes, oceans, and ponds. The heating of this water causes evaporation, which forms in clouds, and comes down again as rain or snow. By knowing about this, you can help kids learn about where their drinking water comes from, and with a few activities, you can teach them all about the water cycle.
Simple Evaporation
To show children about the evaporation part of the water cycle, you can easily demonstrate it with a pot of water and a stove. Let the kids see how the water sits in the pot like it would in a lake or ocean. Then turn on the heat, letting them know that it�s hot, and explain how it represents the sun. They can see the heat warming the water visually by watching the water boil, and then watch the steam disappear into the air as vapor during evaporation.
Indoor Example
Using a glass jar, some rocks, sand, soil, a plant, and a bottle cap of water, you can show your students how the water cycle works in nature. Take a clean jar and fill it half an inch with rocks, then another half inch with sand, and then an inch or two of soil. Plant the plant on one side of the jar, and set the cap of water across from it. This will show how the cap of water will regain liquid, but never more than what had been in it originally. This is a long term project, better for older children.
Creating a Cloud
To create a cloud, you will need a two liter soda bottle with a cap, some water, and matches with adult supervision. A child should be able to pour a little water (just a few drops) inside the bottle, and watch as an adult lights a match, blows it out, and then drops it in the bottle quickly, screwing on the cap tightly. The bottle should then be squeezed hard for a minute, and then released to reveal the cloud inside. The adult can then explain that the heat from the match and the closed bottle warmed the water enough that it evaporated. When the pressure was released, the vapor formed a cloud.
Condensation
Showing students condensation is easy. Of course they�ve all seen a glass of water sweat on a hot day, but this will help them see the actual process and not just notice the wet glass. Take a paper-sized sheet of cardboard or a book and put it in the freezer for an hour. Then heat up a tea kettle or pot of water until there is a good amount of steam going. Place the cold cardboard in line with the steam so that the students can watch water droplets form on the cardboard. This will show them condensation.
Precipitation
In conjunction to the condensation activity, you can also show the students or children how precipitation works. Take the cardboard from the condensation experiment and continue to watch the condensation even after a good amount has formed. Have a pie tin or some other container ready and when the cardboard has too much condensation on it, get ready to catch the water in the pie tin. This will show the students how the condensation turns into precipitation.
Teaching children about the water cycle is the first step in them learning about water conservation and pure water. By teaching them about how water returns to the lakes and oceans they drink from, the students can learn how they get clean, healthy tap water in their homes.