# 2.4 Addition and Subtraction on the Number Line

## Unit Goals

- Students learn about the structure of a number line and use it to represent numbers within 100. They also relate addition and subtraction to length and represent the operations on the number line.

### Section A Goals

- Represent whole numbers within 100 as lengths from 0 on a number line.
- Understand the structure of the number line.

### Section B Goals

- Represent sums and differences on a number line.