Target Number Machine
This makes a great partner starter activity.
The games gives children plentyty of practice in addition and subtraction of two digit numbers, and a simple development means it can also be used to reinforce place value and decimal numbers.
The gameboard features a series of cells representing three two digit numbers:
To play the game, the boards should be cut out and laminated. Children then write on them with a whiteboard pen. The players also need a set of 0-9 digit cards between them.
The idea of the game is to create a number sentence which totals as close as possible to 50. The digit cards are shuffled and one is dealt face-up, the players each choose where to write that digit on their own gameboard. A second digit card is revealed and again players decide where to place this new digit. This continues until all 6 cells of the board are completed. Players then calculate the answer to the additon and subjtraction problem they have created - the one with the asnwer closest to 50 is the winner.
Once a digit has been written on hte board it cannot be erased or moved. This means that the players have to think carefully about their choice of position. In the example below the player ended with a total close to 50... however, if he had chosen to place the '8' as a 'ten' instead of a 'unit' his resluting total would have been very different. This encourages children to think ahead at each turn. The game is a more complex development of the mathsticks High Number Game.
The game could be simplified for some children by allowing them to select 6 random digit cards and look at them all before starting to write their numbes on the gameboard - this focusses more on strategy and calculation and relies less on luck.
The game can also be developed further by allowing the children to place decimal points on the gameboard after all of the numbers have been written:
The downloadable pdf contains a coloured and a black and white version in two different sizes:
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