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Unit 8 - Lesson 15 - Grade 3: Illustrative Mathematics

By Formative Library
Last updated 2 months ago
11 Questions
Note from the author:
Grade 3 Unit
Lesson 15: Number Talk
CC BY 2021 Illustrative Mathematics®
Grade 3 Unit
Lesson 15: Number Talk
CC BY 2021 Illustrative Mathematics®
Lesson: Number Talk

Number Talk: Addition (Warm Up)

Find the value of each expression mentally.
1.

300 + 400

2.

300 + 437

3.

321 + 437

4.

425 + 514

Number Talk Design 1

Here are three subtraction expressions.
  • 600 - 400
  • 600 - 399
  • 500 - 399
5.

Think of at least two different ways to find the value of each difference mentally.


6.

Write a fourth subtraction expression whose value can be found using one of the strategies you thought of.

Number Talk Design 2

Here are two addition expressions.
  • 500 + 199
  • 504 + 199
7.

Think of at least two different ways to find the value of each sum mentally.


8.

Write two more addition expressions whose values can be found using the strategies you thought of.


Number Talk Design 3

9.

Write three subtraction expressions to complete the Number Talk.
  • 900 - 400


Number Talk Design 4

10.

Write four addition or subtraction expressions to create a Number Talk.


Cool Down: Number Talk Reflection
11.

As mathematicians, we use patterns and things we see happening over and over again to help us reason about new problems. Describe a time today where you did that.