The Importance of Water
Students learn that water is essential to life. Discover many places that water can be found on Earth. Learn about the different forms of water in the ground and in the air. Follow the water cycle, and learn how clouds form. Understand many ways we use water including bathing, cooking, transportation, and food production.
Learn that water is essential to life and discover the many places water can be found on Earth and the many ways we use water.
- Students will recognize that water is the most abundant liquid on earth. Earth is called the "water planet". Water covers seventy percent of the earth's surface.
- Students will know that water is present above ground in rivers, streams, lakes, and oceans. However, water is also present under the earth's surface in underground streams, known as ground water.
- Students will understand that water is also present in the atmosphere. Water insulates the earth by protecting it from the sun's heat and by preventing heat from being lost too quickly.
- Students will realize that water can exist in a liquid, solid, or gaseous state.
- Water as a liquid: Rain, puddles, ponds, lakes, streams, rivers, oceans, and ground water are examples of water in its liquid state.
- Water as a solid: This includes sleet, frozen rain, snow, and ice.
- Water as a gas: This invisible gas is known as water vapor.
- Students will understand the parts of the water cycle.
- Evaporation: First, water is heated by the sun. This heated water is converted into water vapor. The conversion of water from a liquid to gas is known as evaporation. Evaporation occurs all the time, and all over the world. However, most evaporation occurs over the oceans.
- Condensation: Once the water evaporates, it cools and forms on tiny particles of dust and pollen. This process is known as condensation. Condensation creates the clouds we see in the sky.
- Precipitation: When the clouds become too large and too full of water, the water falls to the earth in the form of precipitation. Rain, sleet, snow, hail, and drizzle are all forms of precipitation. After the water falls to the ground, the cycle begins again.
- Students will know that all living things require water for their survival.
- Plants are the only organisms that can synthesize their own food, but they need water to do so. Plants return water to the atmosphere through transpiration — water evaporates from their leaves.
- Animals, including people, require a lot of water. In fact, seventy five percent of the human body is composed of water. Animals use water to digest food, to carry nutrients to the cells, and to carry off waste products.
- Students will understand that people use water everyday. Drinking, preparing food, and bathing are all human uses for water. Water is also used for transportation. For example, we ship the rice we grow to Japan by boat. In addition, water is used for recreational activities like swimming, skiing, and snowboarding.
- Students will know how we obtain water for human use. We get water using reservoirs, wells, pipes, and irrigation.
- Reservoirs slow or stop the natural movement of water. This is usually done by building a dam. Once the water is stopped or slowed, a reservoir is created from which people can get water.
- Wells are holes dug into the ground that allow people to bring groundwater to the earth's surface.
- Pipes carry water from reservoirs or wells to people's homes.
- Irrigation is the use of water to grow crops. Ditches or canals direct water from a river, stream, lake, or reservoir to fields of crops.
- Students will realize that water is required for food production. Crops and livestock require food for growth.
- Students will know that water provides us with two types of energy: stored energy and moving energy.
- Stored energy is water that is waiting to become moving energy. Water held behind a dam is stored energy.
- Water that has been released is moving energy. Moving water can be used to spin turbines that create energy.
- Before viewing the video
- Anticipatory Set: Tell students you are going to put a dab of water on their cheeks. They are to raise their hands when their cheeks no longer feel wet. Use a paper towel or cotton ball to apply water. How did it feel? (cold) Where did it go? (evaporated)
- Two Open-ended Webs:
i) What you know about water.
ii) How we use water.
iii) Draw 2 circles on board; write one title in each. Radiate lines from circle to each fact given by the class.
- After viewing the video
- Making a Water Cycle
i) Materials needed: self-heating tea kettle or hot plate & teakettle (with water), 1 cookie sheet, 1 sheet 12" X 18" green paper, ice cubes, 2 large blocks, boxes or chairs.
ii) Setup: Put cookie sheet across 2 blocks. Leave a wide space between blocks. Put green paper (grass) under sheet. Heat up water in advance and put kettle where steam will hit underside of sheet. Put ice on the sheet.
iii) Representations: Steam from kettle is evaporating water. Cold sheet is upper atmosphere.
iv) Facts: When heated water rises, it hits cold upper air and condenses into drops of water. When the water becomes heavier than air, it falls to the ground as rain. When this water evaporates again the water cycle continues!
- Making a Water Cycle
- Liquid, Solid, and Gas
- Water Cycle
- Water is a Basic Need
- How Do We Get Water?
- Water in Manufacturing
- Water Can Change Earth
- Conserving Water