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'Shut the Box' printed from http://nrich.maths.org/
Why do this game?
can give pupils the opportunity to use their number knowledge and it can be adapted to stretch even the highest attainers. In its simplest form it can be accessed by anyone in the class who is able to connect the number of spots on a die to the numeral that represents it. Altering the rules will give
the children opportunities to explore ideas about what makes a "good" game and to develop winning strategies to play their games.
Start with the basic rules and play the game as a class, or perhaps one half of the class against the other, perhaps using large dice. You could use an interactive whiteboard with digits to erase, use "real " pdf larger cards fixed to an ordinary
board with Blu Tack, or you could simply have the numbers written on the board and cross them out. You could also use the interactive version of the game. After playing a few times, encourage the children to be critical of the game. The game offers opportunities for the teacher to identify
the children's understanding the meanings of numbers to $6$ and linking their iconic representation on dice with their numeral.
Pairs of children could then test out the different versions of the game with the aim of explaining why they thought it was good or not so good. This could then lead into a whole-class discussion about features of "good" mathematical games in general. Invite the learners to suggest what else could be changed in the game. Identifying the variables in this way (for example, number of players,
type of dice, number of cards etc) is a useful skill which children can apply again and again. Pairs could test their own version to see whether they have made a good game.
These questions have been phrased in ways that will help the teacher to identify the children's prior knowledge about both the number concepts involved in playing the game and the strategies and mathematical thinking needed to win.
How many spots can you see on the two dice?
Which cards will you turn over?
Can you tell me about why you chose to turn those numbers over?
Strategies, problem solving and reasoning
What is good about the game? What is not so good? Why? How could you alter the rules to make it better?
Which cards could you turn over? Which would be best? Why?
What else could we change about the game?
By giving learners the chance to invent their own rules, children can take responsibility for their own mathematics and demonstrate their potential. You can use $12$ numbered cards instead of $6$ and add, subtract or multiply the scores on the two dice together to find the number to turn over. It may be worth considering changing the rule which ends the turn when double is thrown.
Most children will find it manageable to use numbers $1$- $6$ to start with. Do let them go on to explore their own games, they may well surprise you!