4 Operations on Number

Lesson

- To practise with basic multiplication, addition, and subtraction facts in an engaged way.
- To think critically as to whether addition or multiplication will produce a larger amount.

- Two dice
- Paper and Pen

Work with at least one other partner to play this game. Each group will need one pair of dice.

- Players take turns rolling the dice.
- At your turn, choose whether to keep the sum or the product of the two numbers by telling the other players.
- The sum or product you choose is added to your score (be sure to check that other players are correct!)
- All players begin with a score of 0, and the first player to reach (or go over) 100 points wins!

Optional Rule: If a player rolls doubles then they can subtract the sum of the dice rolled from one of their opponent's scores.

Be sure to record your score throughout the game as well as the calculations that you used to earn all of your points.

1. Did you use addition or multiplication most often when combining the numbers on the dice? Why do you think so?

2. What did you notice about your choice to use addition? When did you find it most useful?

3. Double your final score. What is the result?

4. Compare your doubled score to your opponent’s. Who’s is larger? Why?

5. Is there an easy way to multiply your original score by 20 now that you know the value of your original score when doubled? Explain.

6. Compare with a friend! How were your explanations to question 5 different? How were they the same?

7. Find the value of your original score when it is multiplied by 20.

8. Could you use the same method to find the value of your original score multiplied by 200? What about 2000? If so, what are those values?

Use a range of additive and simple multiplicative strategies with whole numbers, fractions, decimals, and percentages.