1. Getting ready for Addition and Subtraction concepts
Chapter 1
Getting ready for Addition and Subtraction concepts
PowerPoint by Susie Mumper
3rd Grade HES
2011

2. Home Vocabulary Lesson 1.2 Lesson 1.4 Lesson 1.6 Lesson 1.1 Lesson 1.3

3. Lesson 1.6 objective – To use the problem solving skill choose the operation.
Let’s chill out while we practice some math.
Time for some practice. Turn to p. 13 and we will do numbers 1-4.

4. Math task Math book p. 13 numbers 5-7 all.
In your math journal answer this question: Kevin has 56 stamps. Jill has 38 stamps. Write one addition and one subtraction problem using this information.
Remember you need to restate the question in your answer , write in complete sentences and show your work.
Math game from the black box
Home

5. Lesson 1.5 objective – To subtract 2-digit numbers with and without regrouping.
Khan academy subtraction 2
Now let’s practice. Turn in your math book to p. 10 and we will do numbers 2-6 together.

6. Math task Math book p. 11 numbers 7-37 odd
In your math journal answer this question: How does the inverse operation help you in subtraction?
Remember you need to restate the question in your answer , write in complete sentences and show your work.
Math game from the black box
Home

7. Lesson 1.4 objective – To add 2 – digit numbers with and without regrouping.

8. Let’s practice
Turn in your math book to p. 9 and let’s do 2-6 together.

9. Math task Math book p. 9 numbers 7-29 odd
Answer this question in your math journal: How would you add 54 and 28?
Math game from the black box
Home

10. Lesson 1.3 objective – To use properties of addition
What is the order property of addition?
You can add two or more numbers in any order and get the same sum.
6 + 7 = 13 or =13
What is the identity property of addition?
When you add zero to a number, the sum is that number.
2 + 0 = 2 or = 34 or = 259
What is the grouping property of addition?
You can group addends in different ways and still get the same sum.
(9 + 1) + 4 = 14 or 9 + (1 + 4) = 14

11. Let’s practice together
Turn in your math book to p. 7 and let’s do numbers 2-4 together.

12. Math task Math book p. 7 numbers 5 – 21 odd.
In your journal write a number sentence to go with each of the addition properties listed on p. 6 in your math book.
Math game from the black box.
Home

13. Lesson 1.2 objective – To solve number sentences for missing addends.
Today we are going to learn about missing addends.

14. Now let’s practice together
Open your math book to p. 5 and let’s do 2-5 together.

15. Math task MB p. 5 numbers 6-28 even.
Find this missing addends and write them in your journal:
5 + ___= 12
___ + 8 = 10
9 + ___ = 15
Math game from the black box
Home

16. fact family
A fact family is a set of related addition and subtraction number sentences that use the same numbers = – 4 = 7

17. inverse operations
Inverse operations are operations that undo each other, such as addition and subtraction. They are opposites.

18. Order Property of Addition
The order property of addition states that when you add two numbers in any order, you get the same sum = 13 and = 13

19. Identity Property of Addition
The identity property of addition states that when you add zero to a number, the sum does not change = 12

20. Grouping Property of Addition
The grouping property of addition states that when you add three or more addends in different ways, the sum stays the same. (9 + 1) + 4 = 9 + (1 + 4) = = 14
Home

21. Animals on Brittany’s farm
Lesson 1.1 Objective – To identify and write related addition and subtraction facts
The pictograph shows some of the animals on Brittany's farm
Animals on Brittany’s farm
Chickens
Cows
Ducks
Sheep
Key: Each = 2 animals

22. How many duck and chickens are there?
Animals on Brittany’s farm
Chickens
Cows
Ducks
Sheep
Key: Each = 2 animals
Let’s skip count the ducks by 2’s. Ducks =
Now let’s do the same thing for chickens. Chickens=
Now let’s add them together.
So 8+6=14 or 6+8=14

23. The numbers 6,8 and 14 can be used to make a fact family.
What is a fact family?
A fact family is a set of related addition and subtraction number sentences that use the same numbers.
What are the number sentences in the 6,8,and 14 fact family?

24. Write another fact family that uses the number 8.

25. What is the fact family for 6, 6, and 12?
Why does this fact family only have two facts?

26. Fact families are examples of inverse operations.
What are inverse operations?
Inverse operations are opposites. So addition and subtraction are inverse operations.
What is another example of inverse operations?

27. Let’s practice Get out your math book and turn to p. 3
Let’s do 2-7 together.

28. Math task
MB p. 3 numbers 8-26 even. When you finish stack them neatly in one stack on my desk.
Write the facts for these fact families in your math journal: 4,2 and 6; 6, 2, and 8; 1, 14, and 15; 8, 2, and 10; and 6, 13; and 19.
Math game from the black box.
Home