The game uses a 3x3 square board. 2 players take turns to play,
either placing a red on an empty square, or changing a red to
orange, or orange to green. The player who forms 3 of 1 colour in a
A game for 1 person to develop stategy and shape and space awareness. 12 counters are placed on a board. Counters are removed one at a time. The aim is to be left with only 1 counter.
Part the Piles
Age 7 to 11 Challenge Level:
This is a game for two players.
Begin with a pile of counters. (It might be a good idea to start with, for example, 7 counters.)
The first player must separate the pile into two piles each containing a different number of counters.
Player 2 then splits one of these piles into two unequal piles.
Players take it in turns to separate the piles like this.
The winner is the player who makes it impossible for his or her opponent to divide any of the piles into two unequal piles.
You may like to use the interactivity to play against a friend. To split a pile of counters, use the mouse to select a group of counters to move into a new pile.
When do you know who will win?
Can you devise a strategy that might help you win?
What happens if you change the number of counters you start with?
This game is a version of the old favourite, Nim. If you enjoy playing it, you may like to play this
different version against the computer. Searching on NRICH for Nim will also bring up some other suggestions.
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.