standard_description: Mentally add 10 or 100 to a given number 100–900, and mentally subtract 10 or 100 from a given number 100–900.
problem_activity: Stage 7: Subtract Hundreds, Tens, or Ones
Required Preparation
Materials to Gather
Number cubes
Materials to Copy
Blackline Masters
Target Numbers Stage 7 Recording Sheet

Narrative
Students subtract hundreds, tens, and ones to get as close to 0 as possible. Students start their first equation with 1,000 and take turns rolling three cubes to get a number to subtract. For each number they roll, they choose whether they want it to represent hundreds, tens, or ones. Students subtract their hundreds, tens, and ones from the starting number. The difference becomes the first number in the next equation. The player who gets closest to 0 in 6 rounds, without going below 0, is the winner.
Additional Information
Each group of 2 needs three number cubes.


aligns: yes