Learn some math tricks to help with addition and subtraction.
We will learn these strategies in class, also.

0+0=0
1+1=2
2+2=4
3+3=6
4+4=8
5+5=10
6+6=12
7+7=14
8+8=16
9+9=18
10+10=20

2. The "Human" Number Line

7+12=

3. Order property: The order of the numbers in anaddition problem does not change

7+12 = 12+7

Both of these sums are the same! The answer is 19!

4. Doubles plus one: You can figure the sum of 7+8 if you know your double 7+7=14.

Just add one more to the answer because 8 is one more than 7.

7+8 = 7+7+1

5. Adding Ten is easy: When you add a number to ten, just take out the "0" in the

number 10 andreplace it with the number you are adding to it.

10+6=16
10+5=15

6. Make a nine a ten. It is faster when adding if you make a ten out of the problem.

9+6 is the same as 10+5
9+7 is the same as 10+6
9+8 is the same as 10+7

Remember what these mean also...

- to take something away
= is the same as

Subtraction Strategies

You will learn some strategies in class to help you subtract quickly.
Practice them at home until you know them by heart.

The fact family 3,7,4 has three members in it. They are:

3+4=7         4+3=7
7-4=3          7-3=4

7-3 = ? What number plus 3 will equal 7?

2. Subtract nothing from a number and the number stays the same.

8 - 0 = 8             9-0=9              4-0=4

3. Use a number line to count back to find the answer.

9 - 5 = ?... Start at 9 and count back 5 spaces on the number

4. Use a number line to count forward to find the answer.

sentence. In the number sentence 6-4,