How to use this sheet

  • Let the child answer aloud before writing. Mental math is about the thinking, not the pencil.
  • Ask "How did you do it?" after a few answers, and share another way to do the same one.
  • Encourage jumps to a friendly number first: 38 + 5 is 38 + 2 + 3.

Common mistakes

  • Trying to do the column method in their head and losing digits. Use friendly numbers instead: tens first, then ones.
  • Adding the tens and forgetting the ones, so 30 + 24 becomes 50. Say both parts aloud.
  • Rounding to make it easier and then forgetting to adjust back. If you added 2 to make a ten, take 2 away at the end.

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