To help students recognize equivalent fractions, ask students to fold their pink halves strip to show 1/2. Fold the other strips to show the same part of the whole. See Figure 8.
Explain that fractions are equivalent if they represent the same part of the whole. Ask students to show and name fractions equivalent to 1/2 and list their responses on the board: 1/2, 2/4, 4/8.
Ask students to find other pairs of equivalent fractions.
- Show a fraction that is equivalent to 2/8. (1/4)
- Show a fraction that is equivalent to 3/4. (6/8)
- Show fractions that are equivalent to 1. (2/2, 4/4, 8/8)
- How do you know these fractions are equivalent? (When I fold the strips to show each fraction, each strip is the same length or has the same area or represents the same part of the whole.)
Next ask students to answer Questions 6–8. In these questions, they find equivalent fractions by referring to a picture of a fraction chart made from fraction strips. In the next lesson, they will make larger fraction charts by pasting their strips (along with additional strips they will make in that lesson) onto paper.
After students have completed the questions, say:
- Show me a fraction equivalent to 1/4. (2/8)
- Write a number sentence to show this.
(1/4 = 2/8 or 1/4 = 1/8 + 1/8 )
- Show me a fraction equivalent to 6/8. (3/4)
- Write a number sentence to show this.
(6/8 = 3/4 or 6/8 = 1/4 + 1/4 + 1/4)
- Is this number sentence true:
1/8 + 1/8 + 1/8 + 1/8 + 1/8 + 1/8 = 1/4 + 1/4 + 1/4? How do you know? (It is true because both sides of the equation show the same or equal amounts.)
Equivalent Fractions. In mathematics, two fractions that have the same value are considered equivalent fractions. On the fraction strips, equivalent fractions are two that show the same length. This term is discussed more fully in Lesson 5 of this unit, after the students have become more familiar with the basic concepts of fractions. At the fourth-grade level, we do not distinguish between the words equal and equivalent. Therefore, it is acceptable for students to use either equal or equivalent when comparing two fractions that have the same value.
