The
Shadow Knows: Teacher Notes
![](i/shadows.jpg)
![](i/sss.gif)
MA.7.A.1.1
MA.7.A.1.6
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Conceptual Knowledge
Ratios
Proportions
Measurement
Procedural Knowledge
Measuring Lengths
Solving Proportions
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Problem Solving
Reasoning
Communication
Connections
Representation
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Can you determine the height
of a telephone pole or tree without climbing to the top?
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Students work in groups
of 3 or 4
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- 1 short metric measuring
tape
- Sunshine
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- Choose two students from your group. Measure their heights and the
lengths of their shadows. Record your data in the table below.
Student
Name
|
Height
|
Length
of Shadow
|
|
|
|
|
|
|
- Measure the length of the 3rd and 4th students shadows. Record
their data in the table below.
Student
Name
|
Length
of Shadow
|
|
|
|
|
- 3. Use the measurements in a ratio to predict the height of the
3rd and 4th students.
Formula:
Height
of Student 1
|
=
|
(x)
Height of Student 3
|
Length
of Student 1s Shadow
|
|
Length
of Student 3s Shadow
|
Cross multiply and divide to find student 3s height.
Repeat for student 4.
- Pick a nearby object (tree, telephone pole) and measure its shadow
length. Use the previous ratio to find the height of the new object.
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As a result of this activity,
students will be able to determine heights of objects that cannot
be directly measured.
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Compare results from different
group findings.
What applications would this activity have in the business world?
What occupations would need this skill to do their job?
|