Unit 7, Lesson 2
Points on the Number Line
Grade 6
Preparation
Lesson Narrative
In this lesson, students examine and make use of the structure of the number line (MP7). Students begin by considering which values could be represented by a point on a horizontal number line by reasoning about the position in relation to other known values on the number line. Then they revisit the context of temperature, represented on a vertical number line, extending previous work interpreting equally spaced divisions to the negative part of the number line.
Next, students create folded number lines out of tracing paper to reinforce the symmetry of the number line and to reason about opposites—numbers that are the same distance from zero but on opposite sides of the number line.
Lastly, students are introduced to the term rational number as a number that can be expressed as a positive or negative fraction or zero. Students will have more practice placing rational numbers on the number line in future lessons. The focus in this lesson is the concept of opposites rather than plotting different kinds of rational numbers.
- Comprehend that two numbers are called “opposites” when they are the same distance from zero, but on different sides of the number line.
- Interpret a point on the number line that represents a positive or negative rational number.
- Plot a point on a number line to represent a positive or negative rational number.
Let’s plot positive and negative numbers on the number line.
Required Materials
Required Preparation
None
Two numbers are opposites if they are the same distance from 0 on the number line, but on different sides. One is negative, and the other is positive.
A rational number is a number that can be written as a positive fraction, a negative fraction, or zero.
- 8 and -8 are rational numbers because they can be written as and .
- 0.75 and -0.75 are rational numbers because they can be written as and .