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For younger learners

  • Early Years Foundation Stage

Odds and Threes

Age 7 to 11
Challenge Level Yellow star
  • Game

This is a game for two, three or four players.
You will need a pack of cards with the Jacks, Queens and Kings removed. (Ace is a one)

Deal out two cards to each player.
You can add, subtract, multiply or divide the two numbers to make a whole number, or just put them together to make a 2-digit number.

You score one point for making an odd number, OR a number that can be divided by three.

The player who has the most points after five rounds wins the game.

                 

Example: with these cards you could make the following numbers:


  46
 
  64
 
  4 + 6 = 10
 
  4 x 6 = 24
 
  6 - 4 = 2
 


But only 24 would score a point because it can be divided by three.

Can you predict as soon as you get your cards if you will be able to make an odd number?

What's the quick way to tell if a number is divisible by 3?

How could you change the game to make it more challenging?

Printable NRICH Roadshow resource.

You may also like

Number Detective

Follow the clues to find the mystery number.

Prime Magic

Place the numbers 1, 2, 3,..., 9 one on each square of a 3 by 3 grid so that all the rows and columns add up to a prime number. How many different solutions can you find?

Diagonal Trace

You can trace over all of the diagonals of a pentagon without lifting your pencil and without going over any more than once. Can the same thing be done with a hexagon or with a heptagon?

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The NRICH Project aims to enrich the mathematical experiences of all learners. To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice.

NRICH is part of the family of activities in the Millennium Mathematics Project.

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