Size It Up
Adapted from a lesson by Jim Hendrickson

Overview:

This lesson will provide the students with a chance to practice their skills of estimation to develop a better understanding of water/land proportions on the Earth. Students will locate land/water sources on a globe, understand which (land or water) covers more space on the Earth, apply fractions when describing the amount of land/water covering the Earth, analyze the information and apply it to another experiment.

Connection to the Curriculum: Math, Geography

Teaching Level: 4-6

Connection to State Content Standards:

1 Read, interpret and make maps...

Connection to National Standards:

1 How to use maps and other geographic representations.
3 How to analyze the spatial organization of people, places and environments on Earth's surface

Materials:

Plastic blow-up globe
Notebook paper

Procedure:
  1. Have students briefly view a globe, focusing on the land and water mass. Ask students to write down their predictions of whether they think there is more water or more land. Tell the students that they will be tossing the globe around the class until it has been passed 30 times.
  2. Each time a student catches the globe, they record whether their right thumb is touching land or water. Have them estimate how many times water will be chosen and how many times land will be chosen. The teacher records the information for the class to view. (Halfway through, ask the students if they would like to change their predictions.)
  3. After 30 exchanges, review and discuss results.
  4. Ask the students to draw a circle that will represent the Earth. The number 30 will be used to indicate the "whole" circle being filled in. Have the students shade in the circle to show the water amount. Extensions:
  5. Have the students follow the previous procedure and experiment to see which continent will be chosen the most after 30 tosses.
  6. Using a flat map, have students cut out the land and water. Separate the two, glue together on graph paper to view the differences in area.
  7. Using the opaque projector, have the students draw a small-scale representation of the Earth for the classroom floor.
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