Download Addition Fact Strategies

Addition Fact Strategies
By the end of Grade Two, students are expected to recall basic addition
facts with a response time of 3 seconds or less. Strategies aid children in
their recall of facts. Listed below are the strategies we will work on this
year.
Counting On: Students start with the largest number in the equation and
then count on. This strategy is only useful when you are adding 1,2 or 3 to a
number.
For example: 5+2 =
Start with 5 and count on 6,7.
Doubles: The goal is for students to be able to name, quickly and accurately,
the double of any number from 1 to 9. The students have been using visual
clues to think of when trying to remember these double facts.
Double Fact:
4+4
5+5
6+6
7+7
8+8
9+9
Possible Association:
Number of legs on a spider
Number of fingers on 2 hands
Number of eggs in a carton
Number of days in 2 weeks
Number of crayons in two rows of a box
Number of tires on an 18-wheeler truck
Doubles Plus 1 or 2: Once students can easily recall the sum of any double
from 1 to 9, they can use those facts to help them mentally figure out
combinations that are close to a double.
For example: 3+4 =
Think: Double 3 is 6 plus 1 more makes 7
5+7 =
Think : Double 5 is 10 plus 2 more makes 12
Combinations that make 10: Students should practice having quick recall of
the combinations that add to 10.
0 and 10
1 and 9
2 and 8
3 and 7
4 and 6
5 and 5
Once students know these addition combinations to make 10, they will find
them useful in learning other facts.
Example : 8 + 4 = Think 8 + 2 makes 10 + 2 more = 12
Adding with 10: When students are adding 10, the ones digit is staying the
same and the tens digit is increasing by one.
Example: 10 + 5 = 15
7 + 10 = 17
This strategy becomes very useful when we begin adding with larger
numbers. ( Example : 35 + 10 = 45)
Adding with 8 or 9: Once students understand how to add with 10, this
strategy becomes easier to use. This works in 2 steps. First students think
about what the addend plus 10 would be. Then they subtract either a 1 or 2
away from that sum (depending on whether they are adding 8 or 9).
Example: 6 + 9 =
Think: 6 + 10 = 16 so 6 + 9 is 1 less which = 15
6+8=
Think : 6 + 10 = 16 so 6 + 8 is 2 less which = 14
OR - Another way to add with 8 or 9 is to take away 1 or 2 from the one
addend to make the 9 or 8 addend a 10, and then adding this 10 to what was
left from the other addend.
Example : 9 +7 =
Think: Take 1 from the 7 to make the 9 a 10, and
then add 10 and 6 to get 16.