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Watery Planet    Mystery 1

Mystery 1 image

In this Mystery, students use estimation and graphing to discover the surprising difference in the amounts of fresh and salt water on Earth.

How much water is in the world?

Beginning Exploration (1 of 10)
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Beginning Exploration (2 of 10)

DISCUSS (1 of 2):

Imagine you were floating alone in a boat on the ocean with nothing. What problems would you face? What would you need to survive?

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Beginning Exploration (3 of 10)

DISCUSS (2 of 2):

I’m sure you thought of many problems you’d face, like needing food to survive. What about needing water to survive? Would that be a problem? Why or why not?

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Beginning Exploration (4 of 10)
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Beginning Exploration (5 of 10)

DISCUSS (1 of 2):

List all the ways that you and your family use water. Imagine what your life would be like if this water disappeared. How would things change?

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Beginning Exploration (6 of 10)

DISCUSS (2 of 2):

How much water do you think your family uses in a day?

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Beginning Exploration (7 of 10)
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Beginning Exploration (8 of 10)

DISCUSS (1 of 2): Make a Guess

Do you think there's the same amount of fresh water and salt water on Earth? Or do you think there's more of one than the other? If so, how much more do you think there is? Twice as much? Five times as much? Or some other amount?

Remember your guess for later.

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Beginning Exploration (9 of 10)

DISCUSS (2 of 2):

Can you think of a way to figure out how much of the earth is covered by salt water and how much by fresh water?

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Beginning Activity Prep
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Beginning Activity: Map the World's Water
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Beginning Activity: Map the World's Water
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Beginning Activity: Map the World's Water
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Beginning Activity: Map the World's Water
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Beginning Activity: Map the World's Water
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Beginning Activity: Map the World's Water
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Beginning Activity: Map the World's Water
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Beginning Activity: Map the World's Water
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Beginning Activity: Map the World's Water
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Beginning Activity: Map the World's Water
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Beginning Activity: Map the World's Water
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Beginning Activity: Map the World's Water
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Beginning Activity: Map the World's Water
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Beginning Activity: Map the World's Water
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Beginning Activity: Map the World's Water
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Beginning Activity: Map the World's Water
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Beginning Activity: Map the World's Water
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Beginning Activity: Map the World's Water
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Beginning Exploration (10 of 10)
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Beginning Complete!

You've completed the Exploration & Activity!

If you have more time, view the assessment, reading and extension activity in the optional extras.

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Optional Extras

Below are ideas for extending this topic beyond the activity and exploration you just completed.
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Activity: “Can You Spare a Drop?”

Give students a hands-on feel for how little fresh water is available on Earth with this activity from the University of Michigan.

All you need are:

  • a bucket of water
  • a few measuring cups
  • an eyedropper

This activity includes supporting information and teacher tools. It's fully aligned with the Next Generation Science Standards.

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Readings

These readings are free with registration at Newsela. Articles can be adjusted for reading level. Writing prompts and quiz questions are also available.

  • In this reading, students discover what air bubbles trapped in ice can tell us about the earth’s atmosphere hundreds of thousands of years ago. (Grade 4, also in Spanish)

  • Can toilet water be turned into tap water? Here’s a reading that will REALLY get your students’ thinking about conserving water. (Grade 6)

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Videos on Icebergs and Oceans

  • “What’s Below the Tip of the Iceberg?” (4:51) — Learn how icebergs form and move and create floating islands of fresh water where unexpected life can flourish.
  • “How Big Is the Ocean?” (5:25) How much water is in the ocean? A lot. Hiding under all that water are the world’s longest mountain chain, largest waterfall (yes, it’s underwater), tallest mountain, and deepest canyon.

Click the link below each video for lesson ideas based on the subject. A free subscription to TED Ed gives you access to additional resources, discussion questions, and more. These videos can build your students’ vocabulary. (There are a few advanced words.)

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Discuss — Why do some places use more fresh water than others?

Look at this map from the U.S. Geological Survey. It shows how much fresh water different states in the USA used in 2005. Dark-blue states used more water than light-blue ones.

  • Can you think of some reasons that some states use more water than others?
  • Could climate have anything to do with water use?
  • Do more people live in one place than another?
  • Do people do different types of work in different parts of the country?
  • Can you find your own state? Why do you think it uses the amount of water shown here?
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Image & Video Credits

Mystery Science respects the intellectual property rights of the owners of visual assets. We make every effort to use images and videos under appropriate licenses from the owner or by reaching out to the owner to get explicit permission. If you are the owner of a visual and believe we are using it without permission, please contact us—we will reply promptly and make things right.

Other
goldfish in fishbowl by Image used under license from Shutterstock.com: r.classen
seawater blue by Pexels , used under Public Domain
washing hands in sink by Image used under license from Shutterstock.com: Thanakorn Hongphan
girl drinking water by Image used under license from Shutterstock.com: picturepartners
groceries by Pixabay , used under Public Domain
planet earth by NASA , used under Public Domain
pouring orange juice into bottle by Image used under license from Shutterstock.com: somsak suwanput
caught fish in wooden crates by Image used under license from Shutterstock.com: dzorikto
cup of tea by Image used under license from Shutterstock.com: Africa Studio
fisherman by Image used under license from Shutterstock.com: somsak suwanput
jellyfish held in hand by Image used under license from Shutterstock.com: Valeriia Serykh
sprite can by Image used under license from Shutterstock.com: Abramova Elena
coffee in paper cup by Image used under license from Shutterstock.com: Africa Studio
scuba diver under water by Pixabay , used under Public Domain
boat in ocean by Pexels , used under Public Domain
great white shark by Image used under license from Shutterstock.com: Elsa Hoffmann
interior blue bathroom by Image used under license from Shutterstock.com: Artazum
great white shark fin above water by Image used under license from Shutterstock.com: Sergey Uryadnikov
running shower head by Image used under license from Shutterstock.com: Telekhovskyi
hand scooping water by Image used under license from Shutterstock.com: Janis Smits
toothbrush under running water by Image used under license from Shutterstock.com: rodimov
flushing toilet by Image used under license from Shutterstock.com: Timin
video of vast ocean by OG Pyro
salt and salt shaker by Image used under license from Shutterstock.com: Yulia Furman
small boat in the ocean by Image used under license from Shutterstock.com: Pushish Images
irrigation of farmland by Image used under license from Shutterstock.com: Rudy Umans
gray map of the united states by Image used under license from Shutterstock.com: Miceking
hand scooping water by Image used under license from Shutterstock.com: hidesy
salt shaker by Image used under license from Shutterstock.com: Nature Art
buckets of water by Image used under license from Shutterstock.com: Sutichak
crystal geiser bottle by Webstaurant Store , used under Public Domain
rain cloud by Image used under license from Shutterstock.com: Sergey Nivens
faucet by Image used under license from Shutterstock.com: ILYA AKINSHIN
water bottle by Image used under license from Shutterstock.com: Bluskystudio
running faucet by Image used under license from Shutterstock.com: Saran Jantraurai
blurry man holding umbrella by Image used under license from Shutterstock.com: CHOKCHAI POOMICHAIYA
grand teton national park by Image used under license from Shutterstock.com: Pung
icebergs by Image used under license from Shutterstock.com: leospek