Multidigit +/- (Adding/Subtracting)

Uses composition of tens and all previous strategies to solve multidigit +/- problems.


You may see this:

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Other Examples:

  • Asked, "What's 37 - 18?," says, "I take 1 ten off the 3 tens; that's 2 tens. I take 7 off the 7. That's 2 tens and zero...20. I have one more to take off. That's 19."
  • Asked, "Whats 28 + 35?," thinks, 30 + 35 would be 65. But it's 28, so it's 2 less: 63."

Help your student become a(n) Multidigit +/- (Adding/Subtracting)

These activities challenge children to solve multidigit addition and subtraction problems. Use of algorithms is one goal, but so is flexible use of strategies and relational thinking (e.g., "99 + 99? That's like 200 and then take away 2--198").

Make Me 100

Jumping to 100


Coin Dice

Five Six in a Row

Special Thanks To

Institute of Education Sciences
The research reported here was supported by the Institute of Education Sciences, U.S. Department of Education, through grant numbers R305K050157, R305A120813, R305A110188, and R305A150243. to the University of Denver. The opinions expressed are those of the authors and do not represent views of the Institute or the U.S. Department of Education.