# Fractions / Comparing Units

Activity 15 of 15
This lesson helps students to understand that the size of a fraction will vary with the scale used to define a unit fraction.

## Planning and Resources

Objectives
Students understand that fractions do not necessarily come from the same whole, which can make a difference in what two fractions represent in terms of length or area.

Vocabulary
scalar multiple

Standard:

## Lesson Snapshot

#### Understanding

Students should understand the importance of recognizing the scale or size of the unit when working with fractions.

### What to look for

Give students time to explore the file using different sized wholes and fractions. Encourage students to explain their reasoning for each of. their answers.

### Sample Assessment

Petre had (1/3) of a 6-inch long candy bar and Sande had (1/2) of 4-inch candy bar. Who had the most candy?

Answer: Petre had 2 inches of his bar because (1/3) of 6 is 2. Sande had 2 inches of her candy bar because (1/2) of 4 is 2. So they had the same amount of candy.

#### The Big Idea

Without knowing what each refers to, (1/2) of one thing can be the same as, more than, or less than (1/2) of another.

### What are the students doing?

Students will compare fractions from different-sized wholes.

### What is the teacher doing?

Be sure students understand how the interaction with the number lines supports the mathematics. Discuss scale with students.