Objectives
- Students will be able to define the terms: fraction, numerator, and denominator.
- Students will be able to write a fraction which tells what part of a region is shaded.
- Students will be able to name the numerator and denominator of a fraction.
- Students will identify equivalent fractions.
- Students will be able to write a fraction in lowest terms.
- Students will be able to compare fractions.
Materials
- Rectangular pieces of paper
- Chalkboard
- Chalk
- Facsimile of a pizza
- Numbers 2,4,1,3 on separate slips of paper
Procedures
- Write the terms: fraction, numerator, and denominator on the board.
- Go over each term and each definition.
- Display the facsimile of a pizza, divided into 8 parts. The pizza is going to be divided at a mock family meal.
- Write the numbers 2,4,1,3 on separate pieces of paper. Have four students each select one slip of paper.
- Give each student the number of pieces of pizza indicated on his or her slip of paper.
- Ask the class how much each person received in both decimals and percent.
- Provide each student with a piece of rectangular paper.
- Fold your piece of paper in half. After you have folded the paper in half, instruct the students to do the same.
- Explain that a fraction is a part of a whole. You have divided a whole piece of paper into two equal parts.
- The students will color one of the two equal parts.
- Ask a student to write 1/2 on the board to show that one out of the two equal parts is now shaded.
- Introduce the vocabulary words numerator and denominator. The numerator is the number of parts shaded and the denominator is the total number of equal parts.
- For those students who have difficulty remembering which is the numerator and which is the denominator, try this memory association technique - In a fraction, one number is UP above the line and one is DOWN below the line. Numerator has a "u" in it and so does up; denominator begins with "d" and so does down.
- Repeat the same activity with pieces of paper, demonstrating 1/4, 3/4, 1/3, 2/3, 1/8.
- Each time, a student should write the fraction on the board and identify the numerator and the denominator.
- Ask students to fold a rectangular sheet of paper in half and color one of the two equal parts. Ask what fraction of the paper is colored (1/2).
- Now have them refold the same paper and then fold it in half once again. Unfold.
- How many equal parts now?(4) What fraction is shaded (2/4 or 1/2) Since the amount of shading has not changed, this means that fraction 1/2 = 2/4. T
- Tell students that 1/2 and 2/4 are two names for the same amount. Therefore, they are equivalent.
- Now have students refold the papers and then fold in half a third time.Unfold. What new fraction have they found that is equivalent to 1/2 and 2/4? (4/8) These three fractions name the same amount.
- Write all of the factors of 24 and 100 on the board. Explain why 24/100,12/50, 6/25 are equivalent fractions. They are the same fractions, only the names change, not the value.
- A fraction is in lowest terms when the numerator and denominator only have the number 1 as a common factor.
- Write the terms unlike fractions and like fractions on the board, explain the definitions. Now, go over the term least common denominator and explain.