Choose a range of numbers. It can be as small as 1-25 or as large as 1-1,000,000. Keeping it to yourself, pick one number from with the range. Your child's challenge is to identify the number by asking questions that can be answered "Yes" or "No".
Each questions should try to eliminate as many numbers as possible until one number is left. For example, if the range is 1-50, your child could eliminate half the numbers by asking, "If the range is 1-50, your child could eliminate half the numbers by asking, "Is the number higher than 25?" If the number you chose was "36,", you would say, "Yes." Using that clue, your child would frame other questions until he or she is ready to announce the mystery number.
Encourage your child to ask broad questions ("Is the number higher than...?" Is it lower than...? Is it lower than....?" "Is it an odd number?" "Is it a two digit number?") instead of just guessing numbers randomly. After each clue, chat about what is now known about the number and how this can help your child thing of what to ask next.
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