Exploding Dots

5.1 Welcome

Lesson materials located below the video overview.

Addition, subtraction, multiplication. Now it is time for division.


Here’s an example of a division problem:  Compute \(276 \div 12\).


And here’s a horrible way to solve it:  Draw a picture of \(276\) dots on a page and then circle groups of twelve dots. You will see, after about an hour, that there are \(23\) groups of twelve in a picture of \(276\).


Here’s a great way to solve it: Draw a picture of \(276\) dots in a \(1 \leftarrow 10\) machine and just see right away that there are \(23\) groups of twelve in it! 


Read and play on to see how we can do this.


Cool Fact: Did you that the division symbol \(\div\) is called an obelus?


Supplementary Content for this Experience:

The overall Teacher’s guide: Teaching_Guide_GETTING STARTED

Teacher’s Guide for this Experience: Teaching_Guide_EXPERIENCE_5

Accompanying Student handouts: Handouts_EXPERIENCE_5

Sprinkled throughout these lessons are kid videos, from Goldfish & Robin and friends, explaining the math for kids too. Here is their vision statement.

BOOK CHAPTERS (The on-screen text as a book to download.)

Chapter 5 EXPLODING DOTS (English)

Chapter 5 EXPLODING DOTS Bulgarian (Translated by Stanislav Chobanov)

Chapter 5 EXPLODING DOTS Chinese (Translated by Xinli Wang)

Chapter 5 EXPLODING DOTS French (Translated by Pierre-Yves Dansereau)

Chapter 5 EXPLODING DOTS Serbian (Translated by Aleksandra Ravas)

Chapter 5 EXPLODING DOTS Spanish (Translated by Cindy Weitzman)


The Global Math Project is honoured to have a number of its partner organizations provide the means to play with and learn about Exploding Dots with newly developed apps, products, and pages especially designed for the project. Click here.  Of course, Scolab (Buzzmath) has the full Exploding Dots story here.


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Guides & Solutions

Dive deeper into key topics through detailed, easy to follow guides and solution sets.


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