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Student Instructions
1. Read the short lesson on regrouping.
2. Learn the key words.
Go to the 
for Math Mammoth , 
your score.
3. Solve the practice problems and show your steps.
4. Do the word problem.
5. Work with a partner on a strategy activity and record your result.
6.When complete 
Teacher Notes (not visible to students)
This activity gives students a short, clear recap of subtraction with regrouping and several practice problems up to the hundreds. Use the practice mode so students get feedback after submission. Encourage students to write each step (hundreds, tens, ones) and to check answers by adding the difference to the subtrahend to see if it equals the minuend. Prepare simple materials for the partner activity: pencil, scrap paper, and counters (e.g., base-ten blocks or small cubes) if available. For the open-ended paragraph, a high-quality answer explains the regrouping steps in order (which place was regrouped from and to), shows correct arithmetic steps, and checks the result. Partial credit answers show correct reasoning but may have minor arithmetic mistakes; incorrect answers lack clear steps or show a misunderstanding of place value or regrouping.
