The curriculum unit “Water, Our Most Important Beverage,” is written for a third grade class as part of the social studies and science curriculum. In 3rd grade the New Haven public schools study the community and its resources and government. Students also learn about the natural resources of the area and how good citizenship is important to the success of our local and national governments. In science we explore the earth and its resources, as well as the principles of scientific inquiry which includes developing the powers of observation, predicting outcomes, and interpreting data. Our students also study recycling and conservation. Both of these larger curriculum areas can be taught through a curriculum unit in water.
My students are inner city children who like many of us have thought little about our drinking water and where it actually comes from. Many of them would predictably say that water comes from the tap at the sink or out of the water fountain. While the unit seeks to show them the wider picture of where water comes from, it also seeks to make them understand that we are truly tied to nature through our basic need of water. Without water there would be no life on the earth. The supply of water we have is limited by nature. It is not always where we want it when we want it. And we know that due to increasing use of chemicals and the improper disposal of these chemicals often shows up in our water supply. As the world population escalates we have an increased need for a resource that is necessary for all life on this planet. Our dependence on this natural resource makes it imperative that students be encouraged to advocate for laws and standards that will keep our waters safe. They will someday be in charge of these resources and education is the best way to ensure that they include the safety of our drinking water as part of the responsibility of being a good citizens.
The following is an outline of the contents of the unit:
I. Earth’s Water
A. How much water is on the earth?
B. Where is the Earth’s water located?
II. Local Water
A. Where do New Haven and its neighbors get their water?
B. What is done to the water to make it safe to drink?
III. The Rain Cycle
A. How does the rain cycle work?
B. How does rain water get polluted?
IV. Problems Facing Our Water Supply
A. contaminants
B. governmental legislation
C. Public involvement
V. How Can We Help?
A. How do students and their families use water?
B. What can students do to conserve water at home and in school?
As a way of introducing the unit I will begin with one of the basic concepts taught in 2nd and 3rd grade social studies, namely needs versus wants. In studying the community and how it functions students are taught that people must balance their needs and wants. In this case water is a definite need but as they shall see there are difficult choices which must be made if the supply of clean drinking water is to be maintained.
Students will be asked to write a few lines about what they know about water and/or contribute their ideas to the development of a class KWL chart (What I Know, What I Want to Know, and What I Learned) to be constructed as the unit develops. The KWL chart is a widely used graphic organizer which helps students focus on what information they are learning when they are dealing with nonfiction topics. A preliminary brainstorming idea to gauge children’s prior knowledge can generate interest in the topic and show students that they already possess a great deal of knowledge about a subject they may not thing they know much about. Children can have individual KWL charts and as for this project I would set up a wall of chart papers to keep track of the information learned. It is a visual reminder to the students of the progress they are making and what still needs to be researched.
Beside a KWL chart the class would begin the building of a word wall of terms that will be important to the unit. In elementary school we often use word walls in reading to show word families, new vocabulary, or different spelling structures. In this case the word wall would list new terms which students are learning while studying the unit and keep them literally right in front of them. They would be there for review and for students to refer to as they prepare reports or complete journal writing assignments.
It would also be beneficial to look at the globe. Most likely students will think what is the problem? There seems to be plenty of water on the earth. Once we begin to delve into the state of earth’s water supply students will soon see that most of the water is unusable by people. For young students nothing helps more than a visual. Try illustrating the relative amounts of water on the earth as opposed to land and usable versus unusable water. This can be easily facilitated by doing either of two activities suggested on the - website. 11
Objective: To illustrate the amount of usable water on the earth.
Materials: 100 ziti macaroni (One could also use 100 Dixie cups filled with water and dyed in a similar fashion with food coloring).
red, green, and blue food dye
Procedure:
The 100 ziti macaroni will represent the earth’s water.
1. Dye 97 pieces blue. They represent the water that is in the oceans.
2. Dye one piece green. It represents the amount of water available for plants, people, and animals.
3. Dye 2 pieces red. They represent the water stored in glaciers and at the poles.
4. Spread the macaroni out so that student can see the proportions.
Earth’s Water
Since the earth does not lose any of its water into outer space its water system is a closed system very much like that of a terrarium. Virtually all the water that exists now has existed for ages, and was here even when the dinosaurs roamed the earth. Basically, water is continually moving around the earth as water vapor, liquid water, and ice. The water cycle provides for water to be continually recycled around the globe.
While two thirds of the earth is water, over 99 per cent of this water is not usable. Of the 0.3% left much of that is not available for our use. The vast amount of fresh water available to us is stored in the ground. The earth’s total supply of water is about 326 million cubic miles of water. Surface-water sources (such as rivers) only make up about 300 cubic miles or 1/10,000th of one percent and yet these rivers are the source of most of the water we use. 2
|
Water Source
|
Water Volume, in cubic miles
|
Percent of total water
|
|
Oceans
|
17,000,000
|
97.24%
|
|
Icecaps, Glaciers
|
7,000,000
|
2.14%
|
|
Ground Water
|
2,000,000
|
0.61%
|
|
Fresh water lakes
|
30,000
|
0.009%
|
|
Inland seas
|
25,000
|
0.008%
|
|
Soil Moisture
|
16,000
|
0.005%
|
|
Atmosphere
|
3,000
|
0.001%
|
|
Rivers
|
300
|
0.0001%
|
|
Total water volume
|
326,000,000
|
100% 3
|
Because we take for granted that water will be there whenever we turn on a tap we tend to dismiss any notion that our water supply could be in danger. The ancient peoples and those who live in third world countries probably share a better perspective on the situation than we do. They live each day concerned about rainfall and unclean water. As far back as recorded history people have struggled with the necessity to provide clean water to the rest of the population. In ancient drawings it is apparent that the Egyptians were using a variety of methods to remove impurities from the water. The Roman engineers developed a water supply system that delivered 130 million gallons of water daily through aqueducts. 4
For earlier peoples if the water was clear it was presumed to be clean and safe to drink. The 16th and 17th centuries were marked by many significant scientific discoveries. However, even though Anton Van Leeuwenhoek invented the microscope during this time it would be nearly two hundred years before the scientific community would realize that the tiny microscopic organisms he sketched were capable of carrying diseases into the water supply. Not until the 1870’s when Dr. Robert Koch and Dr. Joseph Lister demonstrated this process would water treatment processes be aggressively pursued. This led to the beginning of a recognition that the community had to ensure a supply of quality drinking water. The development of water filtration in here was interrupted by the Civil War, but once that was concluded the United States became a leader in the art of water treatment.5
In 1908 the Bubbly Creek plant in Chicago started regular use of chlorine disinfection. In 1942 the U.S. Public Service adopted the first set of drinking water standards, and the membrane filter process for bacteriological analysis was approved in 1957. 6It soon became apparent that there were serious treats to maintaining a safe supply of drinking water. As a result, in 1974 the enactment of the Safe Drinking Water Act finally linked the government, the public health community, and the water utilities throughout the country to work together to safeguard the water supply in the United States. Its purpose was to govern the quality of drinking water in rural areas as well as large urban centers. In 1986 this Act was revised, calling on the EPA to help enforce the regulations.7
In 1977 the Federal Water Pollution Control Act was amended and was commonly know as the Clean Water Act. This act established the foundation for trying to control the pollutants that were directly discharged from homes or businesses into the waters of the United States. It also financed wastewater treatment plants and tried to help manage polluted runoff. The purpose was to clean up waterways so that fish and other wild life could be restored to their natural habitats and to make these waters recreation places for citizens to use.8
The history of water is an interesting sidebar to the topic of clean water. For elementary age students the concept of time and how they fit into it is difficult to understand. We are always encouraged to use timelines as a way of explaining history to our students. I suggest a classroom timeline which may or may not be partially or totally produced by students depending on their ages, capability, and available time. For my third graders I would most likely choose some important people and events from the history of water (as well as relevant events from the history and city) and have them research their importance. Then each child would make a poster containing an explanation of the event or person along with the appropriate date or dates. I would use a series of ropes which are hung around my room to be the actual time line. It would be marked with signs showing the centuries. Students would actually build the timeline by hanging their posters around the room in the appropriate spot.
In trying to connect state and local history to the study of the local water supply I think Lynne Cherry’s book “A River Ran Wild” is an excellent story. It tells of the Nashua River and how it existed during the days before the European settlers came. The Native Americans lived along the river and respected it taking only what they needed and keeping a balance going. The 1600s mark the coming of European settlers and eventually industrialization and takeover by the colonists. In the ensuing years the river became over used, smelly and polluted. In the 1960s a grass roots effort led by a woman named Marion Stoddart fought to see the river cleaned up.9
The story of the Nashua River and the settling of Massachusetts are similar to that of the settlement and growth of Connecticut. Here the early settlements were influenced by the available rivers from the Connecticut to the Thames, Housatonic and locally the Quinnipiac. In both states the Native Americans were pushed off their lands as a result of what is known as King Philip’s War. The early agrarian society soon gave way to the expanse of industrialization from textiles to gun making, hat production, silver crafting, and later aviation industries. Locally the Quinnipiac River became polluted from upstream industrialization much like the Nashua. I think this story gives a nice way of organizing the chronology of the problem. 10
