Create Your Own Number Line

10 min

Narrative

This Warm-up prompts students to compare four images. It gives students a reason to use language precisely (MP6). It gives the teacher an opportunity to hear how students use terminology to talk about characteristics of the items in comparison to one another. During the discussion, ask students to explain the meaning of any terms they use, such as “tick mark,” “label,” “unit fraction,” “whole number,” and “length.”

Launch

  • Groups of 2
  • Display the image.
  • “Pick 3 number lines that go together. Be ready to share why they go together.”
  • 1 minute: quiet think time
Teacher Instructions
  • “Discuss your thinking with your partner.”
  • 2–3 minutes: partner discussion
  • Share and record responses.

Student Task

Which 3 go together?

A

B

C

D

Sample Response

Sample responses:

A, B, and C go together because:
  • They use fractions to label whole numbers that are not 0.
  • They have a point to show a location on the number line.
A, B, and D go together because:
  • They have 5 tick marks.
  • They have 4 intervals or lengths between tick marks.
  • The last tick mark is labeled with whole number.
A, C, and D go together because:
  • They have a label that shows a unit fraction. 
B, C, and D go together because:
  • They use fractions with denominators of 2.
  • The length from 0 to the last tick mark on the line is more than 1.

Synthesis

  • “Why do all 4 go together?” (All are number lines. All have labels written as fractions. The length between tick marks on each number line is the same. All start with and label 0.)
Standards
Addressing
  • 3.NF.2·Understand a fraction as a number on the number line; represent fractions on a number line diagram.
  • 3.NF.A.2·Understand a fraction as a number on the number line; represent fractions on a number line diagram.

25 min

10 min