32

Using the TI-73: A Guide for Teachers

Patterns

Activity

Have students perform the steps unless otherwise indicated.

1.Make each large marshmallow into a Martian head by poking 2 toothpicks on it and adding 2 small marshmallows to the tops of the toothpicks for antennas.

2.Starting with one Martian head, make a T-chart to show how many heads and how many antennas. An example of the start of a T-chart follows.

# Martian

# Antennas

Heads

 

1

2

2

4

.

.

.

.

5

 

 

 

3.See if the students can see a pattern in their own 5 Martian heads. Ask: What if we were to count antennas in the entire classroom? Is there a fast way to count them up?

Students can use the @ key to try their fast rule.

Example If students decided the rule was to add 2 antennas each time, then they would enter

-† (above the @ key)

\ Z - l

Y @ Z @ (and continue putting in the number of Martian heads and pressing @ until they get to 5)

See if this matches their T-charts. Students will probably discover that for every marshmallow Martian head, there are 2 times as many antennas.

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