Lesson 2 How Did You Add?

- Let’s add numbers and find matching equations.

Warm-up Choral Count: Count Back From 70

Count backward by 1, starting at 70.

What patterns do you see?

Activity 1 Find the Value

Find the value of $23 + 45$ .
Show your thinking using drawings, numbers, or words.

Activity 2 Elena and Andre Represent 63 + 25

Here are 2 drawings students made for $63 + 25$ .

Elena’s work

Andre’s work

Which equations go with which drawing?
Be ready to explain your thinking in a way others will understand.

Set A
$63 + 20 = 83$
$83 + 5 = 88$

Set B
$60 + 20 = 80$
$3 + 5 = 8$
$80 + 8 = 88$

Activity 3 Introduce Five in a Row: Add Within 100 without Composing

We are going to learn a new way to play Five in a Row.

Practice Problem

Problem 1

Find the value of $31 + 24$ .
Show your thinking using drawings, numbers, or words.