Lesson: Subtract Whole Numbers (Lesson 2)
Count backwards (orally) by ones from ten, by threes from 30, by tens from 100.
Tell students that they did a great job counting backwards. Tell them that if they can count backwards, they can subtract.
- State objective.
- Review subtracting without regrouping.
- Explicitly tell students that when the top number is bigger than the bottom number in each column, you do not have to regroup.
- Model subtracting with regrouping.
Subtract the following:
First, set each problem up vertically by "stacking" numbers into their appropriate column. Then, ask will you need to borrow? If yes, ask in which place.
Exit Questions: In the problem 3,452-128, do you need to borrow? Explain and then find the difference.
|Subtracting Whole Numbers Lesson 2 Quiz 1 Other||