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Read numbers to three or more decimal places (including numbers greater than 1)

Decimal Mastermind

Timeframe: 10 minutes warm up game

Audience: 2 players or whole class

Materials: Paper/pencil and/or whiteboard

Summary: The Mastermind chooses a 3 or 4 digit decimal number and the player must try and determine the number by using the green tick, black dot or red cross clues from the Mastermind. A green tick means the correct number in the correct place value column, a black dot means it is the correct number in the incorrect place value column, a red cross means the digit is not in the Mastermind’s number at all. The player usually has to determine the number correctly within 10 moves. The player must say the decimal number correctly to be a valid turn eg. 0.123 is not read as ‘zero point one hundred and twenty three’, it is ‘zero point one two three’.

Guiding questions: Point out black dots or green ticks in previous turns if the class is struggling to achieve the correct answer.

Source: unknown

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