Knock Off Numbers for Mental Math Practice!

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What You Need:

  • 1 die
  • paper
  • pencil

What You Do:

  1. With your child, do a quick “warm-up” review of addition facts to 10. Use flashcards or just quickly write out some facts on paper.
  2. Give your child the die. Ask her to roll it 10 times. Each time she rolls the die, write down the number she rolls. You will end up with a vertical list of 10 numbers.
  3. Next, explain to your third-grader that she will be learning a way to add the 10 numbers quickly and without writing anything! Help her find 2 numbers in the list that add to 10, such as 4 and 6. Model for her what to do. Say, “4 +6 = 10” and cross out the 4 and 6 while you say it. Then look for 2 more numbers in the list that add to 10, such as 5 and 5, and repeat the process. Once you’ve added all pairs that add to 10, add 3 digits to get 10. Say, “2 + 5 = 7, 7 + 3 = 10” and cross out the numbers you used. Explain that now you’re up to 20 and add the remaining numbers to get a total.
  4. Continue practicing mental math with your third-grader. Have her roll the die as you record the numbers, then watch as she crosses out the numbers and “talks” her way through adding the list.  Make it fun and competitive by timing how long she takes to add the list mentally. After you time her, challenge her to “beat her time” on the next list. A small reward for beating her time is always a good incentive, too!

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