Lesson 7-- Mental math

Introduction

Welcome back Mathematicians! Today, we will practice "mental math." Mental math is a way of doing math only in your head, without using tools like counters or drawings.

Video

Take a look at the arrangement of dots in this video. Then answer the following questions in your math notebook:

How many dots do you see?
How do you know?
Do you see it more than one way?

Now, watch this solutions video. Did you see any of these groupings?

Interactive

Directions:

Click the link below to watch the slideshow. It will play automatically.
Some images are dot arrangements, some are photographs.
Get ready to quickly make mental groups to determine the total amount.
For a challenge, watch the show again and see if you can make different groups.

Mental Math Slides Deck

[CC BY 4.0] UNLESS OTHERWISE NOTED | IMAGES: LICENSED AND USED ACCORDING TO TERMS OF SUBSCRIPTION

From Georgia Department of Education, Math