Iceberg!: Teacher’s Guide
Grade Level: 6-8
Curriculum Focus: Earth Science
Lesson Duration: Two class periods
Program Description
Scientists and engineers have been trying to control and destroy icebergs for decades. In this video
you’ll see some of these attempts and learn why they all ultimately failed. Then, travel through
“Iceberg Alley” for some hot news about how global warming might actually lead to dropping
temperatures worldwide!
Onscreen Questions and Activities
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Pre-viewing questions:
o
What do you know about icebergs? Where do they come from? What kinds of
dangers do they pose?
o
As you watch the documentary, pay attention to the physical structure that makes
icebergs unique. Why does an iceberg get stronger the deeper you go beneath the
water surface?
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Post-viewing questions: Research has shown that global warming is increasing the number of
icebergs released into the Labrador Current. Discuss the long-term effects of global warming
and brainstorm possible ways to prevent the phenomenon.
•
Activity: Measure the volume and mass of water in a film canister. Then freeze the water in the
canister and measure the volume and the mass of the ice. Using the data you collect, explain
why ice floats.
Lesson Plan
Student Objectives
Students will understand:
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As glaciers move, they create a variety of patterns on landforms by a process called glacial
scraping.
•
The scraping patterns left by a glacier depend on how the glacier moved over the landform.
Iceberg!: Teacher’s Guide
•
2
The evidence of glaciation left by glacial scraping provides clues to the climate in a particular
place over a long period of time.
Materials
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Iceberg! video and VCR, or DVD and DVD player
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Access to a freezer
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Photographs of glacial-scraping patterns
For each group:
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Plastic cup
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Pieces of sharp, angular gravel
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Tap water
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Plastic wrap
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Tape
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Paper plate
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Smooth piece of wood
Procedures
1. Review with your students what they have learned about glaciers. They should be able to
define glacier and explain why glaciers move over landforms.
2. Ask students how they think scientists can tell if glaciers have moved over the land in a
particular area. Explain that rocks and gravel freeze into the ice and are dragged over the land
by the bottom surface of a glacier. How would the land over which a glacier has moved be
affected? What evidence of glaciation do glaciers leave behind?
3. Tell your students that they will participate in an activity that will simulate the way landforms
are affected by glaciation.
4. Divide the class into groups, and have each group create its own miniature glacier as follows:
a) Have students half-fill a paper cup with sharp, angular gravel.
b) Cover the gravel with about an inch of water.
c) Securely tape plastic wrap over the top of the cup.
d) Flip the cup onto a paper plate.
e) Leave the inverted cup in a freezer overnight.
5. When the “glaciers” are frozen solid, have students peel off the plastic wrap and paper cup and
scrape them, gravel end down, over a smooth piece of wood. To simulate the action of a glacier,
students should scrape in only one direction, since glaciers move only one way.
Published by Discovery Education. © 2005. All rights reserved.
Iceberg!: Teacher’s Guide
3
6. Ask students to observe the patterns the gravel has made on the wood. How would they
compare these to the patterns made on landforms by a real glacier? Explain that when glaciers
move, they create a variety of patterns on landforms by a process called glacial scraping. (If
possible, provide photographs of actual glacial scraping.)
7. Have each student sketch their patterns and write a short paragraph explaining what they can
infer about the way real glaciers affect the landforms over which they move.
8. Discuss with the class how patterns of glaciation provide clues to the climate in a particular area
over time. For example, if evidence of glacial scraping is found in an area that is too warm for
glaciers to exist, what can we infer about how the climate in that area has changed over a long
period of time?
Discussion Questions
1. Speculate why icebergs are so hard to destroy. List your reasons.
2. Water expands when it freezes. This is the underlying reason why an iceberg floats—it is less
dense than water. So, why does the amount of underwater ice in an iceberg vary?
3. If you were a ship’s captain and had to sail into iceberg-infested waters, what precautions
would you take?
4. Speculate whether icebergs could be used constructively as a resource for freshwater.
5. Discuss thermohaline circulation and its global effects.
6. Analyze the global effects of the current annual increase in icebergs. Relate the analysis to
present-day processes.
Assessment
Use the following three-point rubric to evaluate students' work during this lesson.
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3 points: Student’s sketches carefully and accurately drawn; paragraphs clear, complete, and
error-free.
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2 points: Students’ sketches adequate; paragraphs sufficiently clear, but with some errors.
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1 point: Students’ sketches adequate; paragraphs lacking in clarity with numerous errors.
Vocabulary
Bergie seltzer
Definition: Air bubbles released from melting icebergs.
Context: Bergie seltzer is released when icebergs melt as they drift along in Baffin Bay. The
fizzing noise is produced because the air bubbles are under high pressure.
calved
Definition: Separated or broken so that a part becomes detached.
Context: One million tons of ice are calved each day from a 300-foot glacial wall.
Published by Discovery Education. © 2005. All rights reserved.
Iceberg!: Teacher’s Guide
4
enigmatic
Definition: Mysterious or obscure.
Context: Icebergs are enigmatic. How they move, how thick-skinned they are, how much
damage they can do are all subject to debate.
sea ice
Definition: Frozen seawater.
Context: Sea ice forms when part of the sea freezes.
Thermohaline circulation
Definition: A circulation of seawater resulting from a combination of temperature and salinity
effects.
Context: Thermohaline circulation is the conveyor belt that brings warm water to northern
Europe.
Academic Standards
Mid-continent Research for Education and Learning (McREL)
McREL's Content Knowledge: A Compendium of Standards and Benchmarks for K-12 Education
addresses 14 content areas. To view the standards and benchmarks, visit
http://www.mcrel.org/compendium/browse.asp.
This lesson plan addresses the following national standards:
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Science—Earth Science: Understands Earth's composition and structure.
National Academy of Sciences
The National Academy of Sciences provides guidelines for teaching science in grades K-12 to promote
scientific literacy. To view the standards, visit this Web site:
http://books.nap.edu/html/nses/html/overview.html#content.
This lesson plan addresses the following national standards:
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Earth Science: Structure of the earth system
Support Materials
Develop custom worksheets, educational puzzles, online quizzes, and more with the free teaching tools
offered on the Discoveryschool.com Web site. Create and print support materials, or save them to a
Custom Classroom account for future use. To learn more, visit
•
http://school.discovery.com/teachingtools/teachingtools.html
Published by Discovery Education. © 2005. All rights reserved.