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How do you send a secret code?
Waves of Sound Unit | Lesson 1 of 4

How do you send a secret code?

Waves of Sound Unit | Lesson 1 of 4
Lesson narration:
Scroll for prep
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DISCUSS:
What do you notice is the same about all the barcodes?
Do you notice any kind of pattern?
DISCUSS: How do you think the scanner translates the black and white pattern into something the computer understands?
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DISCUSS:
What’s the same about these two patterns? What’s different?

DISCUSS:

If you made your own secret code out of ANY two things, what would you use?

Step
01/23
You’ll work with a partner.
Decide who will be Decoder A and who will be Decoder B.
Step
02/23
Get your supplies.
Step
03/23
Get your Snack Decoder. Look closely at the pattern of black boxes
and white boxes for each snack item.
Step
04a/23
Practice Round: Watch carefully. Use the back of your Snack
Decoder to write down what you see. Discuss with your partner
what my secret snack might be.
Step
04b/23
Here’s what you might have noticed.
Step
05/23
Before you brainstorm, you need to know the CRITERIA for success
and the CONSTRAINTS of what your code can be. Look at what
materials you have for making your new codes.
Step
06/23
Both: Brainstorm different visual patterns you could use for your
code. Write down all your ideas on the back of the Visual Code
worksheet. Try to come up with at least four different ideas!
Step
07/23
Both: Discuss your ideas and choose your favorite one. Write that on
your Visual Code worksheet in section 1. Make sure that you and your
partner have the same information written down.
Step
08/23
Both: Brainstorm different sound patterns you could use for your
code. Write down all your ideas on the back of the Sound Code
worksheet. Try to come up with at least four different ideas!
Step
09/23
Both: Discuss your ideas and choose your favorite one. Write that on
your Sound Code worksheet in section 1. Make sure that you and
your partner have the same information written down.
Step
10/23
Both: Prepare materials. Remember, you need two sets of materials
because you’ll be standing apart from your partner. You can also use
this time to practice listening to your sound code!
Step
11/23
Both: In a moment, you’ll walk to the opposite side of the room
from your partner. Make sure you bring all of your materials with you.
Step
12/23
Both: Silently choose one snack and write “1” next to it. This will be
your visual code secret snack. Then, silently choose a second snack
and write “2” next to it. This will be your sound code secret snack.
Step
13/23
Both: Get your Visual Code worksheet and find section 2. Then, look
at the first secret snack you chose. Write down how you will
communicate your secret snack using your visual code.
Step
14/23
Both: Get your Sound Code worksheet and find section 2.
Then, look at the second secret snack you chose. Write down how
you will communicate your secret snack using your sound code.
Step
15/23
Watch this entire step first. Decoder A: Send the code of your
secret snack to your partner. Decoder B: Write the code on your
Visual Code worksheet in section 3.
Step
16/23
Decoder B: Send the code of your secret snack to your partner.
Decoder A: Write the code on your Visual Code worksheet
in section 3.
Step
17/23
Both: Write down what you think your partner’s secret snack is on
your Visual Code worksheet in section 4.
Step
18/23
Decoder A: Send the code of your sound code secret snack to your
partner. Decoder B: Write the code on your Sound Code worksheet
in section 3. Both: Remember to switch roles.
Step
19/23
Both: Find the snack that equals the code you recorded.
This should be your partner’s secret snack!
Write the snack item on your Sound Code worksheet in section 4.
Step
20/23
Both: Go back to your desks and sit down next to your partner.
Compare your answers. Talk with your partner and compare how
easy or how difficult it was to figure out their visual and sound code!
Step
21/23
Discuss:
Step
22/23
Discuss. Then, complete question 5 on your Visual Code worksheet.
Step
23/23
Discuss. Then, complete question 5 on your Sound Code worksheet.
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DISCUSS:
What do you think the phone changes the pattern of sound into?
Hint: Think about how a barcode scanner sends a message to the store’s computer.
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DISCUSS:
What do you think happens next inside the phone so that your friend can hear your voice? Hint: Think about what your partner did with the code you sent to figure out your Secret Snack.
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pattern


1 of 9

something that happens again and again and again in a way that can be predicted
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code


2 of 9

a system of words, letters, or other symbols that stand for other words, letters, or symbols

transfer


3 of 9

to move from one place to another
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electricity (electrical energy)


4 of 9

a form of energy, such as what usually powers light bulbs
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decode


5 of 9

to take a code and change it to a different form that can be understood

communicate


6 of 9

to exchange information

sound


7 of 9

vibrations that you can usually hear with your ears
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engineer


8 of 9

a person who uses science to come up with solutions to problems
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inventor


9 of 9

someone who comes up with something new, often an object or a way of doing something
🎉 That’s it for this lesson! How did it go?
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Lesson narration:

Grade 4

Sound, Waves, & Communication

Pattern Transfer & Technology

4-PS4-3, 3-5-ETS1-3

Activity Prep

Print Prep
In this lesson, students explore how digital devices encode complex information so that it can be transferred over long distances. In the activity, Secret Snacks, students generate their own codes in order to transfer information across the classroom. Then, they compare their codes and evaluate which worked best given the criteria and constraints.
Preview activity

Exploration

15 mins

Wrap-Up

15 mins

Grade 4

Sound, Waves, & Communication

Pattern Transfer & Technology

4-PS4-3, 3-5-ETS1-3

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