Materials needed: - Smartboard file from Mr. Dozal’s webpage
Worksheet: Working with Binary
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Video clip from you tube from Mr. Dozal’s webpage
 Pass out Worksheet Activity “Working with Binary”
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Instruct students to tear off the five dot cards at the bottom of the worksheet and separate into five separate dot cards.
 Ask the students to lay out the cards in descending order on their desks, with the highest number of dots on the left and the lowest on the right.
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Lead the following discussion with the class:
What do you notice about the number of dots on the cards?
Each card has twice as many as the card to its right.
How many dots would the next card have if we continued to the left?
32
The next three cards?
64, 128, 256
We can use the cards to make numbers by turning some of them face down and adding up the dots that are showing. Show me how to make 6 using your dot cards. The 4-dot and 2-dot cards should be showing
Show me 15. The 8-dot, 4-dot, 2-dot and 1-dot cards are face up.
Show me 21. The 16-dot, 4-dot, and 1-dot should be face up.
Let’s try counting from zero onwards using our cards. How would we do it?
Ask one or two students to come up to Smartboard and demonstrate counting from zero up using the premade Smartboard file. Students should follow along with their dot cards.
Who sees a pattern in how the cards flip? Each card flips half as often as the one to its right.
(Continued on next page)

When a card is not showing, it is represented by a zero. When it is showing, it is represented by a one. This is called the binary number system, which is how computers make ALL their calculations. Let’s see if you can match your cards with 01001. Which cards should be face up? The 8-dot and the 1-dot card should be face up. Point out this is the number 9. So the number 9 represented in binary is 01001.
What would 17 be in binary? 10001
How about 5?
00101
20? 10100
Is there more than one way to get any number? No
What is the biggest number you can make with the dot cards? 31
Smallest? 0
Is there any number you can’t make between 0 and 31? No. You can make every number in between, and each one has a unique representation.
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Have students answer the questions on the worksheet.
 If time permits, show the video clip on Mr. Dozal’s website and ask students to see if they can follow along with her as she counts on her fingers in binary.