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NCTM Standard: Patterns and Relationships
Objectives: a. The learner will know all the factors of numbers 1-20.
b. The learner will demonstrate understanding by creating factor sticks with all the factors of each number on the stick.
Materials: 25 tongue depressors for each student, black markers, paper, and pencil

Purpose:
The purpose of this lesson is to create factor sticks with which students can practice and have a visual aid to help with greatest common factors. It might also help understand the concept of greatest common factors.

Instructions for creating factor sticks:
On the top of the stick you put the number. Draw a line under the number to separate it from the bottom part of the stick. Then list the multiples of that number one right under the next. For example take the number 5. With the stick standing vertical, you would write the number 5 on the top 1/4 of the stick. Draw a line under it. Then the next number would be 1. Then think out loud (what is 1 times 5. The answer is 5. Write a 5 on the bottom part of the stick. Those are the multiples of 5. Take 18. 18 on the top of the stick. The next number is 1. The bottom number is 18. The number under the 1 is a 2. The number above the 18 is a 9. The number you would write under the 2 is a 3. The number you would write above the 9 is a 6, because 6 X 3 = 18! The least common multiples are there on the stick. The student can use these when reducing fractions!

Anticipatory Set:
Dress up as a dentist. Explain that they are going to be dealing with tongue depressors in math, but first they have to pay attention to how they are going to use them.

Instruction:
*I will have the students get a piece of notebook paper out of the desk and a pencil.
*As a class we will discuss the factors of the numbers 1-10.
*Each student will write them on their paper. We will make a chart like this:
Number       Factors
      1            1,1
      2            1,2
      3            1,3
etc...
*I will not hand out the tongue depressor until I have shown them what mine look like and how they are made (with the number written on top and the factors written from biggest to smallest going down the tongue depressor)
*The students will not get the depressors until after the guided practice.

Guided Practice:
*The class will finish up the list of factors for the numbers 11-20.

Independent Practice:
*The students will make the factor sticks.

Closure:
Ask the students "What was the best part of this lesson?"
By doing this you should receive several answers that will remind other students of the lesson.

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