Lesson 2-5Adding Three Numbers

Mr. Baker2nd Grade

Today We Will Learn!

• Three or more whole numbers can be grouped and added in any order.

Vocabulary Review

So far, you have always had to add just two numbers together.

Today, you’ll learn what to do if you have to add more than two numbers

together.

Do you ever need to add more than two numbers? When? (keeping score in a game, or adding money)

The Problem!!• Suppose you and two friends are counting

cars that pass by.– You count 6 red cars– One friend counts 5 white cars– The other friend counts 4 silver cars

• What are some different ways to find the sum of 6, 5, and 4?

• Use your connecting cubes to figure out different ways to show this problem.

•How did you add these numbers?

•Can I take the cubes and move the groups of colors around to show a different order?

•Will the number of cubes change?

•Let’s try some more.

Let’s Explore!!

•Create trains using these numbers…

1. My numbers are 1, 3, and 2

2. My numbers are 4, 2, and 8

3. My numbers are 5, 3, and 5

4. My numbers are 7, 4, and 1

•Use your work mat to record your answers.

Let’s Explore!!

Let’s Explore!!

Learning Bridge!

• In this lesson, you will learn how to add three numbers.

• Let’s watch and learn!– CLICK HERE– (After learning bridge use guided practice page to continue lesson.)

Close

• In this lesson, you learned that the sum of three numbers will be the same no matter what order you add them.

• You looked at the three numbers and chose the two numbers you wanted to add first.

• Then you added the third number to that sum.

• GREAT JOB!

Math Journal & Technology• Write two different ways to add 3 + 5 + 7.

• Write two different ways to add 6 + 4 + 2.

• On your I Pad go to the math folder and begin working on Cloud Math.