By Megan Joyner
Grade 8: Understanding Earth and Space Systems Water Systems (watersheds)
Lesson Focus (Overall Expectations)
Big Idea: Water is crucial to life on earth and water systems influence climate and weather patterns. More specifically, after being introduced to the idea that water is a finite resource, the big idea of the day is, if the earth is known as the water planet, where does our water come from?
Human activity and changes we make to the landscape affect the water quality and health of the watershed in which we live. All land uses have an impact on water quality, either positively or negatively. In this lesson, students will learn about the importance of our watersheds, their structure, and changes within the water tables. It is important for students to learn about the factors that can cause increases, decreases, and contaminations in our watersheds, and thus the water cycle.
Learning Expectations (Specific Curriculum Expectations)
- 3.2 demonstrate an understanding of the watershed as a fundamental geographic unit, and explain how it relates to water management and planning.
- 3.3 explain how human and natural factors cause changes in the water table (e.g., lawn watering, inefficient showers and toilets, drought, floods, overuse of wells, extraction by bottled water industry).
Lesson Objectives (Learning Goals)
- Gain a visual perspective on the connectivity of watershed systems.
- Draw connections between the contours of their palms and the connectivity of local water systems and watersheds.
- Discover one of the negative impacts of water systems (i.e., contaminants in the water pollute all connected systems).
1. Student’s ability to orally express their knowledge of connected water systems will be assessed.
2. Student’s drawings will be assessed by examining the pictures taken on their electronic device. The drawings will be assessed on student’s ability to follow instructions (i.e., thick, thin, and dotted lines).
3. Student’s ability to find and interpret data from Internet sources to explain influences on watersheds will be assessed through the completion of their final paragraph.
Prerequisite Knowledge and Skills
Before commencing this lesson, students should have had lessons on the different forms of water which exist on earth and should be able to recognize that water isn’t necessarily as available as it seems. Through prior teachings, students should know the following vocabulary: precipitation, rain, snow, sleet, hail, water cycle, and evaporation. In this lesson, students will be introduced to the concept of watersheds and the effects of pollution.
To complete this lesson, students will need to have practice using iPads within the classroom and be reminded of the rules of safe Internet use. If there are only a few students with the ability to use iPads, group students according to skill level/ confidence using the particular electronic device. Note about equity: If your school does not have the use of iPads, you may do this on a desktop computer instead, and use digital cameras or smartphones for the photos.
• Washable blue markers
• Soap (to wash students’ hands)
• Wax paper
• Food colouring
• Dish soap
Markers should all be non-toxic. Soap should be plain and unscented.
The Ontario Curriculum, Grades 1-8: Science and Technology, 2007.
(To be done about 15 minutes before the Learning Activity)
Turn a soup bowl upside down and place it onto a cookie tray. Take a large piece of wax paper and crumple it up. Uncrumple it without taking out all of the bumps and place it over the bowl to make a rather rough hill or mountain. Let the paper lay out over the cookie tray as well.
Use a paper towel roll to angle the tray a bit.
For best results, put 2 or 3 drops of food colouring on the top of your “mountain”. Pour 15-30 mL (1-2 tablespoons) of dish soap on top of the food colouring and observe where it flows. Two to four watersheds (streams of water travelling down the wax paper) should be created. Examine all aspects of the watershed, streams, rivers, lakes…
To demonstrate how poison affects both persons upstream and downstream, use an eyedropper to drop a small amount of a different colour at the top of the water source and watch its path.
NOTE: Due to the nature of the activity, students who are not allowed to draw on their bodies or for religious reasons feel they cannot complete the task on their hands, have these students trace their hands on a piece of paper, and then mirror the lines on their hands onto the paper.
(During) The Learning Activity —“It’s all in your hands”
1. Using WASHABLE markers (OPTIONAL), have students trace the curvatures in the palms of their hands. Have the students make a thick mark on the deepest curvatures on their hands. Next, have the students mark thinner lines for every line leading to that main line.
2. Thickest line on your hand – Grand River (the largest watershed in our area). It is the largest river entirely within southern Ontario’s boundaries. The river owes its size to the unusual fact that it has its source relatively close to the base of the Bruce Peninsula, yet flows southwards to Lake Erie, rather than to central Lake Huron or Georgian Bay (most southern Ontario rivers flow into the nearest Great Lake, which is why most of them are small), thus giving it more distance to take in more water. NOTE: This analogy is based on the Grand River watershed, but could be adapted for other watersheds and other lakes.
3. Parallel to thickest line on your hand – Speed River
4. Small wrinkles in your hand – streams, creeks, marshes or other wetlands
5. Blue Veins – Underground water systems (wells, aquifers) – have students trace these systems using dotted lines.
6. Base of your fingers (“palm knuckles”)– mountains and hills (which all water drains down and off of towards the water systems)
7. Scars – If students have a scar on their hand, it would represent a dried up water system – a river, stream or lake which once had water in it, but is now barren and dry.
8. 5 fingers —- Great Lakes (Note: It is very hard to see the small creases that lead to the fingers. It might cause some confusion as to whether or not water would flow into these “lakes.” You may wish to discuss this with your class.
9. Space outside of your hand —- oceans. Everything drains to the oceans.
Discuss how these lines represent the rivers, streams, lakes, mountain sides, and drains which all run to the same body of water (the ocean), and how our lines run to the side of our hand, and out into the ocean of the rest of our body.
*Dismiss students in small groups to wash their hands.
* If students have electronic devices available, have them take a picture of their hand or a friend’s hand. This can act as a personal anchor chart.
It is important for students to understand that scientists often use models to replicate systems in the real world through a simplified version.
After the Learning Activity (Closure)
Google Earth – iPads or computers
• In this activity, students will take the knowledge gained from the first two activities on watersheds and apply it to investigating a watershed in another region, one perhaps they are not as familiar with (e.g., somewhere in another part of Canada or in the United States).
• Alternative versions of Google Earth are available, but for the purposes of this activity, we will use the free version. It would be most beneficial to have Google Earth on each iPad or computer before beginning the lesson.
• Using iPads in pairs or individually, have students launch Google Earth and select the layers list – checking off the box in front of borders and labels (turn this layer on).
• Allow some free time for exploration. After some trial and error, have students click on elevation layer”. Next have students turn “landcover” and “population images” off.
• In the stream layer, turn on the largest streams, then sequentially have students add the smaller streams by clicking the boxes for streams of decreasing size. Note the patterns that develop. To explore further, turn the smaller stream layers on and off to help visualize the location of drainage divides within the watershed.
• Compare and contrast two versions of the watershed, a zoomed in view and what you saw in your physical watershed model.
• Answer the following question and hand in when completed:
Have students compose a paragraph explaining why they agree or disagree with the following statement; “Only persons downstream in a watershed system need to be concerned about the use and management of their water.”
*Students pack up and get ready for next class.
“It’s all in your hands activity”
Megan Joyner was a pre-service teacher at Wilfrid Laurier University when she wrote this article. Megan was a recipient of the 2013 Don Galbraith Pre-Service Teacher Award of Excellence with this submission.