This exercise continues the discussion of water distribution and availability and adds in visual aids to help students understand the concepts.
NYS/CCL Standards (Content Knowledge, IAD)
Goals: Process Skills (Basic & Integrated) and Attitudes/ (Enduring Understandings & Essential Questions)
Students will gain a visual understanding of a topic they’ve discussed previously. The enduring understanding is a better grasp of the distribution of water around the planet, and what is available for human consumption.
Universal Design for Learning/Differentiation
This lesson is a review, and as such it should allow students that understand the concepts better to volunteer information, while students that are struggling will get another chance to understand the information. Visual aids will also be employed, allowing for a clearer understanding of the distribution of water.
Aquarium or 5 gallon bucket
Shot glass (or small glasses/cups)
Ice cube tray
Estimated Length of Activity:
1 class period (45-50 minutes)
(10 – 20 minutes) Go over different types of water (surface, ground, ocean). Make sure they get a list of terms, and understand each one.
(20 minutes) All the water in the world activity
1. Put 5 gallons of water in an aquarium. Tell students to imagine that the container represents all the water in the world.
2. Ask students to guesstimate what proportion of this water exists on the earth as:
- ground water
- ice caps/glaciers
- freshwater lakes
- inland seas/salt lakes
3. Remove 18 ounces of the water from the aquarium with a measuring cup. Using green food coloring, color the remaining water in the aquarium. Tell the students that this water represents all the water on earth held in oceans. The water in the measuring cup represents all the water in the world that is not ocean water.
4. Pour 15 ounces of the water from the measuring cup into an ice cube tray. This water represents all the water held in glaciers and ice caps. This water is not readily available for our use. Since the amount of water held in the ice cube tray is comparable to that of an ice pack, place the ice pack in the aquarium to represent the total amount of water held in glaciers and ice caps.
5. The remaining 3 ounces represent the world’s available fresh water. Of this amount, a fraction of an ounce is held in the world’s fresh water lakes and rivers. Place this water (approximately one dropper of water) into a student’s hand.
6. The remaining water (approximately 2.5 ounces) is ground water. Pouring this remaining water into a cup of sand, explain that this is what is referred to as ground water and that this water is held in pore spaces of soil and fractures of bedrock. About one-third of New England’s drinking water comes from ground water.
(10 minutes) Follow-up Questions
1. Why isn’t all fresh water usable? Some is not easy to get at; it may be frozen or trapped in unyielding soils or bedrock fractures. Some water is too polluted to use.
2. Why do we need to take care of the surface water/groundwater? Water is very important for humans, plants/crops, and animals. If we waste water or pollute it, we may find that there is less and less of it available for us to use.
There is no formal assignment associated with this lesson.
Assessment and Reflection
Assessment is based on in-class discussion and how students are able to relay their understanding of freshwater distribution.
The visual aid is helpful because the amount of water on the planet is so vast it is hard for students to fully grasp the concept that there are limited supplies. If you can’t use the same materials as listed, there are numerous substitutes that would make this exercise possible, so try playing around with what you have on hand to make the activity work for your class.