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

Sound, Waves, & Communication Unit | Lesson 1 of 4
Lesson narration:
English Spanish
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DISCUSS:
What do you notice is the same about all the barcodes?
Do you notice any kind of pattern?
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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?
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DISCUSS:

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

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Step
01/23
You’ll work with a partner.
Decide who will be Decoder A and who will be Decoder B.
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02/23
Get your supplies.
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03/23
Get your Snack Decoder. Look closely at the pattern of black boxes
and white boxes for each snack item.
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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.
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04b/23
Here’s what you might have noticed.
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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.
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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!
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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.
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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!
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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.
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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!
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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.
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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.
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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.
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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.
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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.
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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.
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17/23
Both: Write down what you think your partner’s secret snack is on
your Visual Code worksheet in section 4.
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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.
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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.
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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!
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21/23
Discuss:
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22/23
Discuss. Then, complete question 5 on your Visual Code worksheet.
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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
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transfer


3 of 9

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


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


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


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to exchange information
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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
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Lesson narration:
English Spanish

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
Number of students:

I have a Mystery Pack

Snack Decoder worksheet 30 copies
Sound Code worksheet 30 copies
Visual Code worksheet 30 copies
Engineering Materials
Students will need materials for their visual and sound codes. At a minimum, we suggest crayons and paper. You can include other items like flashlights, musical instruments, and other materials to encourage student creativity.
Details
60 items
Prep Instructions

We suggest students work in pairs. Homeschool students will need a partner for this activity.

Plan Your Space

This activity involves pairs of students working together to create codes and then separating from one another to communicate those codes over a distance. Ideally student pairs will stand across the room from one another, but you may need to modify depending on your classroom.

Select Your Materials

You can choose to provide whatever materials you’d like for students to use for their codes. We suggest at least some paper and crayons. But you can include flashlights, musical instruments, or anything you’d like to encourage student creativity in their visual and sound code creation.

Sensory Warning

This activity involves students communicating through visual and sound cues across the classroom. If you have students who are sensitive to sensory overload, you may want to adjust the activity or create additional constraints (e.g. only whisper sounds) to create a safe space for all students.

Exploration

15 mins

Hands-On Activity

35 mins

Wrap-Up

15 mins

Grade 4

Sound, Waves, & Communication

Pattern Transfer & Technology

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

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