Water Is Cool!
The purpose of the lesson is to visualize water as a finite resource and to discuss why being good stewards of this resource is acting for the common good.
The learner will:
- name places where water is stored around the Earth.
- give reasons why we should care for freshwater.
- copies of handout for each student: Water on Earth
- Materials for the demonstration to model the distribution of water:
- A clear bin to hold 2.5 gallons
- One eyedropper
- One permanent marker
- 8 clear plastic cups
- One 1000mL measuring container
- One 100mL measuring container
Ask, If we were to consider all of the water on the Earth, what percentage do you think is readily available for human use?
Have the learners do a quick-write about one of the following questions, then have a few volunteers share their thoughts.
- How much of the Earth’s surface is made of water? (about 70% known as the “water planet”)
- How much of your body is made of water? (about 60 -70%)
- Why is clean water important? (all living things depend on it)
Fill a glass with water from the tap and place it where students can see it. Ask learners: “Where did this water come from and how old do you think it is?”
Listen to their ideas and reinforce that water on Earth is in a closed system, so the water we have now has always been on Earth cycling through the water cycle and taking many forms.
The Earth is called the water planet because three-fourths of its surface is covered in water. Freshwater (not salty) is only 2.5 percent of the water on earth. Much of that freshwater is trapped in glaciers and snowfields. Since we don't drink or cook or clean salt water, only 0.007 percent of the planet's water is available for human use. The following demonstration illustrates where water is on the Earth.
Gather the measuring materials for the demonstration:
- Clear bin that holds more than 2.5 gallons of water
- measuring containers (100 ml, 1000 ml, eyedropper)
- 8 clear plastic cups labeled as the locations in the Water on Earth handout (ocean water stays in the bin)
Have the students measure and fill the bin and cups for this activity/demonstration. Talk about scale and what each measured cup represents as you fill and compare the cups.
- Fill the clear bin with 10,000 ml of water to represent all of the water on Earth.
- Refer to the Water on Earth handout to measure the designated quantities in the labeled cups. Take the water out of the bin representing all the water on Earth.
Discuss where the water is, whether is is usable, and how it is cared for.
- Evaporation – The process of water changing from a liquid to a gas. This occurs when the sun heats up the water in oceans, lakes, rivers, etc., turning it into vapor, which goes into the air.
- Condensation – The process by which water vapor changes from a gas to a liquid. Water that has been evaporated into the air by the sun gets cold and changes back into a liquid, collecting on tiny particles in the air and forming clouds.
- Precipitation – When enough water has condensed that the air cannot hold anymore, the clouds get heavy and water falls back to the earth as rain, snow, ice or hail – depending on the temperature.
- Runoff – Water returning to the oceans, lakes, rivers, groundwater, etc. by running over the earth to these locations (or soaking into the ground).
- Transpiration – The process by which plants lose water through their leaves (as water vapor) – releasing the water into the air.
Have students write quietly to answer the questions on the bottom of the Water on Earth handout. After 10-15 minutes, discuss their answers.
Discuss the meaning of Common Good. It involves individual citizens having the commitment and motivation to promote the welfare of the community (even if they must sacrifice their own time, personal preferences or money). It means to work together with other members for the greater benefit of all. For example, if families in your neighborhood work to clean up a vacant lot and plant it with flowers to create a neighborhood garden, everyone in the community would benefit from the garden.
Ask students to give examples and explanations of how protecting our freshwater supply from pollution is related to the common good.
Create a classroom newsletter detailing why water is important and why it is necessary to take care of it.The newsletter could include such aspects as an informational piece, a letter to the editor, a comic strip, and a game or puzzle using vocabulary from the lesson. Share the newspaper with others in the school, parents and the community.
Strand PHIL.I Definitions of Philanthropy
Standard DP 01. Define Philanthropy
Benchmark E.3 Recognize that citizens have a responsibility for the common good as defined by democratic principles.
Strand PHIL.II Philanthropy and Civil Society
Standard PCS 03. Philanthropy and Economics
Benchmark E.13 Describe limited resources and scarcity.
Benchmark E.5 Recognize the wise use of resources as <i>stewardship</i>.