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The "Calculator:"

1. Places a penny in the "start" box and gives it a push with the flick of a finger in the direction of one of the numbered squares.
2. Records on the slate the number on which the penny lands.  (If the penny touches more than one square, the "Calculator" records the smaller number.)
3. Gives the penny another push from where it landed and records the new number on which the penny lands.
4. Adds the two numbers and records their sum on a quarter-sheet.

The "Checker" then:

1. Checks the sum using a calculator.

 

If the sum is correct, the "Calculator" gets a 10-point bonus.  If the sum is incorrect, the "Calculator" corrects the sum on the quarter-sheet.

After five rounds, play stops and players use their calculators to find the sums of their five scores.  The player with the higher total wins.

NOTE:

You may want to change the numbers on the Shuffleboard Mat to provide practice suited to the needs of your children.