The document discusses regrouping or borrowing in subtraction. It explains that regrouping involves taking ten from one number to give to another when subtracting two numbers where the number being subtracted is larger than the number it is being subtracted from. Examples are provided to demonstrate regrouping, and an interactive game asks the reader to identify when regrouping is necessary in subtraction problems. The document concludes by recapping that regrouping is needed when the number being subtracted is larger than the number it is being subtracted from.

1. Subtraction with Regrouping
By: Kathrina Russell-Stubbs

2. Q: What is regrouping?
A: Regrouping or burrowing is a word
which we use to take ten from one
number to give to another. We do
this when we do not have enough to
subtract two numbers.

3. Q: How do you know when to regroup?
A: You know its time to regroup when
the number you are subtracting is
larger than the number which you are
subtracting from.

4. Here are some examples.
2 5
- 1 8
5 cannot take away 8.
So we must burrow
from the 2.
1 15

5. Here are some examples.
5 1
- 4 9
1 cannot take away 9.
So we must burrow
from the 5.
4 11

6. Let’s Play a Game!
Should you regroup?
Click Yes or No.
Continue

7. Should we burrow? Click Yes or No.
6 9
- 5 6
Yes No
Help!

8. Should we burrow? Click Yes or No.
6 9
- 5 6
Yes No

9. Think: 9 – 6. Do you have enough?
9
- 6
Continue

10. Correct
Continue

11. Correct
Continue

12. Incorrect
Continue

13. Incorrect
Continue

14. Should we burrow? Click Yes or No.
4 6
- 1 8
Yes No
Help!

15. Should we burrow? Click Yes or No.
4 6
- 1 8
Yes No
Help!

16. Should we burrow? Click Yes or No.
4 6
- 1 8
Yes No
Help!

17. Should we burrow? Click Yes or No.
4 6
- 1 8
Yes No
Help!

18. Should we burrow? Click Yes or No.
4 6
- 1 8
Yes No

19. Should we burrow? Click Yes or No.
4 6
- 1 8
Yes No

20. Should we burrow? Click Yes or No.
4 6
- 1 8
Yes No

21. Should we burrow? Click Yes or No.
4 6
- 1 8
Yes No

22. Think: 6 – 8. Do you have enough?
6
- 8
Continue

23. Think: 6 – 8. Do you have enough?
6
- 8
Continue

24. Think: 6 – 8. Do you have enough?
6
- 8
Continue

25. Think: 6 – 8. Do you have enough?
6
- 8
Continue

26. Correct
Continue

27. Incorrect
Continue

28. Correct
Continue

29. Incorrect
Continue

30. Correct
Continue

31. Incorrect
Continue

32. Correct
Continue

33. Incorrect

34. Let’s Recap! How do we know when to burrow?
When the number we are subtracting is larger than the number we are
subtracting from.
3 6
- 2 7
___
2 16
90

35. See you next time!

36. Let’s Recap! How do we know when to burrow?
When the number we are subtracting is larger than the number we are
subtracting from.
3 6
- 2 7
___
2 16
90

37. See you next time!

38. Let’s Recap! How do we know when to burrow?
When the number we are subtracting is larger than the number we are
subtracting from.
3 6
- 2 7
___
2 16
90

39. See you next time!

40. Let’s Recap! How do we know when to burrow?
When the number we are subtracting is larger than the number we are
subtracting from.
3 6
- 2 7
___
2 16
90

41. See you next time!

42. Let’s Recap! How do we know when to burrow?
When the number we are subtracting is larger than the number we are
subtracting from.
3 6
- 2 7
___
2 16
90

43. See you next time!

44. Let’s Recap! How do we know when to burrow?
When the number we are subtracting is larger than the number we are
subtracting from.
3 6
- 2 7
___
2 16
90

45. See you next time!