1. 2.NBT.5 Place Value Addition and Subtraction
Feel free to do 1 or a couple of slides per day and then add your own.

2. Add Mentally Be ready to explain how you thought about your answer
13 + 8
Student 1 Decomposing
= 18
and then I counted up 3 = 21
Student 2 Making ten and then counting up
= 20
Plus one more left over from the 8 = 21
Students may think of more ways

3. Add Mentally 14 + 15 Student 1 Adding tens and ones 10 + 10 + 9 = 29
Student 2 Creating easier sums Doubles
= 30 so = 29
Other ways are possible

4. Add Mentally 26 + 24 Student 1 Making ten 20 + 20 + 10 (6+4) = 50
Student 2 Doubles or thinking of money
I know = 50
26 has 1 over 25 and 24 has one less so they both equal 25

5. Add Mentally 17 + 12 + 24 Student 1 example 10 + 10 + 20 = 40
7 + 6 (2+4) = I know 7 plus 7 is 14 so is 13
= 53

6. Add Mentally

7. My friend added mentally and showed their work below
My friend added mentally and showed their work below. Is my friend correct?
First I added and got 70
Then I added 8 Plus 2 to get 10
Then I added 5 more
So, my total is 75

8. True or False Discuss with a partner=

9. Subtract Mentally 37 – 18 Student 1 Making 10’s 37 – 10 = 27
27 – 7 = 20
20 – 1 = 19
Student 2 Counting / Number line
= 28
is 28 which is 1 too many so
jumps on a number line = 19

10. Subtract Mentally share your answer and strategy with a partner
45 – 27

11. Subtract Mentally

12. Is this a correct way to solve the subtraction problem?
62 – 35
60 – 35 = 35
35 – 2 = 33
The answer is 33

13. True or False
56 – 34 = 20

14. Which word problem describes the Number Sentence?
23 – ? = 11
I have 11 cupcakes left after bringing the class 23. Some student were absent. How many students were absent?
23 students were in the class and 12 more joined the class.
I had 23 pencils and some rolled off my desk. I had a total of 11 still on my desk. How many rolled off?