Fractions

Subject:

Math

2, 3

OBJECTIVES

Students will be able to write a fraction to describe what part of a region is shaded. They will also be able to name the numerator and denominator in a fraction. Finally, students will be able to identify equal fractions.

MATERIALS

Plain white paper cut in circles

Chalkboard

Chalk

Anticipatory Set:

-Imagine that you had a pizza and you wanted to share it with 7 of your friends. How would you divide that pizza up so that each of you received an equal amount? Tell students that through this activity, they will learn how to divide something into equal parts by learning about fractions.

Activity for Concept Development:

Day 1:

1. Give each student a piece of plain white paper and request that they fold in in half.
2. Explain that you have divided a whole piece of paper into two equal parts and that a fraction is simply a part of a whole.
3. Ask the students to color in one of the two equal parts, and have one student write ½ on the board to chow that one out of the two equal parts is now shaded.
4. Now is a good time to introduce the numerator and denominator.
5. Explain that the numerator is to be the number of parts shaded and that the denominator is the total number of equal parts.
6. Students might also remember the association better if you explain that down and denominators both start with D.
7. After you have given this instruction, perform the same activity with pieces of paper to describe fractions such as ¼, ¾, 1/8, 2/3, etc. Each time this is done, have students write the fraction on the board and identify the numerator and denominator.

Day 2 (or later in day 1):

1. To teach equivalent fractions, have students take out the paper they had folded in half to demonstrate the fraction ½. Have them fold it again to divide the paper into fourths.
2. Ask them to unfold the paper and describe what they notice.
3. If students do not catch on, explain to them that they have divided the paper into fourths and that 2/4 of the paper is shaded and that this is equal to ½. Another way to do this is to ask what fraction is shaded and students should respond that 2/4 and ½ are both shaded. Since this amount of shading has not changed, this means that ½ is equal to 2/4.
4. Have students fold the same paper in half again to demonstrate that ½ is equal to 2/4 which is equal to 4/8. Follow this up with other equivalent fractions such as 2/3 is equal to 4/6.

Practice:

-Ask students to continue exploring by folding papers and trying to come up with as many different equivalent fractions as they can. This part could be made into a game to increase motivation, with a reward for the winner with the most equivalent fractions. Also request that students identify the numerator and denominator in their examples.

Closure:

-To wrap up this lesson, return to the pizza question presented in the anticipatory set. Question students on what a solution could be for dividing up the pizza to give to 8 people. Most likely, students will realize that the pizza should be cut in half, then cut in half a second time, and then a third time to divide the pizza into 8 equal parts.

Bibliography:

* Lofties, Elizabeth. “CECmath.39.” Big Sky Telegraph Math Lesson Plans .

Reys, R. E., Suydam, M. N., & Lindquist, M. M. (1995). Helping children learn mathematics (4 th ed.). Needham Heights, MA: Allyn and Bacon.

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