Education and
Public Engagement
at the Lunar and Planetary Institute
Explore Earth's Climate

Catch!...the World's Oceans

Adapted from Water Cycle Lesson, and used with permission.

Overview

Children get to know each other through an icebreaker activity that introduces the importance of water on Earth. They stand in a circle and toss a soft Earth globe (such as an inflatable or stuffed globe), noting with each catch that his or her (left or right) index finger usually touches an ocean rather than land. The percentage of Earth covered by oceans — roughly three quarters, or 71% — can be tallied by keeping track of the number of “land” and “ocean” contacts during the game.

What's the Point?

Materials

Facility Needs

For Each Group of 15 Children

For the Facilitator

Background information

Activity

  1. Ask the children what they know about water.
    • How do you use water in your daily life? It is a drink; it’s used for cooking, cleaning, and washing; the grass that we play on and plants that we eat use it to grow; etc.
    • Where is water found on Earth (at or below the surface)? In our oceans, lakes, rivers, and groundwater (and frozen as snow and ice — such as in glaciers, ice caps, and sea ice). Plants and animals — including people — have water inside them.
    • Where is water found in the air? Water is also rain, the tiny droplets that make up clouds, and frozen as snow, hail, and ice. Water is also a gas in our atmosphere (water vapor).
  2. Have everyone stand in a circle and toss the inflatable Earth globe back and forth. Start by introducing yourself and then tossing the ball to someone across from you. Invite each member of the circle to point downward toward the “real” land, and then instruct the children to keep track of where that finger lands on the globe.

    (Note that some children will point with their right index fingers, others will point with their left, or some other variation depending on the child and his or her physical abilities. The children can use any single point on their bodies to keep track during the game…as long as they are consistent!)

      1. For children ages 5 to 7, begin by discussing what the different colors on the ball mean (i.e. land or ocean). Then tell the children that they take turns tossing the ball to each other. When someone catches the ball, (s)he will shout “ocean” or “land,” thank the previous circle member by name, and state his or her own name. Each child will then toss the ball to someone in the circle who hasn’t had a turn, and move outside of the circle to join either an “ocean” line or a “land” line, depending on where his/her finger landed on the globe.  Two lines will form as the game progresses. The game ends after each child has had a turn.

        Which line is longer?  Why? The “ocean” line is likely to be longer, because the Earth has more oceans than land on its surface.

      2. For children ages 8 to 13, have one of the children also serve as record keeper. Tell the children that they take turns tossing the ball to each other. When someone catches the ball, (s)he will shout “ocean” or “land,” thank the previous circle member by name, and state his or her own name. Each child will then toss the ball to someone in the circle who hasn’t had a turn. The record keeper will tally the number of “land” and the number of “ocean” contacts.

        If needed, repeat the game three or more times to gather more data. If repeating, challenge the children to remember the order in which the ball is tossed — as well as the names of the circle members they each receive from and toss the ball to. Finally, calculate the percentage of “ocean” contacts (using a calculator, if desired).

        • What is the percentage of “ocean” contacts for our group?
        • How much of Earth’s surface do you think is actually covered by water? Accept all answers.
        • How does that compare to what we calculated during the game?

  3. Summarize that the children’s index fingers usually contacted ocean; and, indeed, 71% of the Earth’s surface is covered by ocean!
  4. Guide a discussion about how the oceans influence the local region’s weather — even if your region is far from the ocean. With children ages 8 to 13, elaborate that oceans influence winds, evaporate into the air (providing much of the moisture distributed across the globe by clouds), and absorb energy from the Sun — creating our local weather and providing warmth. Oceans help control what kinds of weather an area usually gets (i.e. its climate), such as whether rain, snow, or dry conditions are typical.

Conclusion

Water is an important characteristic or part of our planet!