Lesson: Adding and Subtracting Lengths: Numbers up to 100 Mathematics • 2nd Grade

In this lesson, we will learn how to solve problems to calculate the lengths of objects by adding and subtracting within 100.

Lesson Plan

Students will be able to

use models to find the total length of objects,
use models to find the difference between lengths of objects,
solve simple word problems involving adding and subtracting lengths up to 100 cm,
write addition and subtraction equations representing the problems.

Q1:

Consider the two buildings shown.

Which building is shorter?

How much shorter is it?

Q2:

This paper sheet is 90 centimeters long.

Q3:

2 days ago, Mason’s pencil was 13 cm long. Today, its length is 3 cm less. How long is Mason’s pencil today?