Hillsborough County Public Schools
Elementary Mathematics Parent Connection
Grade 1 – Addition and Subtraction Strategies
In this unit your child will work to build an understanding of adding and subtracting by using the strategies
counting on/back and making a ten.
Counting on to add or back to subtract
 Counting on from a number is the same as adding to that
number.
o Start with the greater addend (number) and count
on using a math tool or fingers to track the change.

5+2=?
Keep 5 in your head and
count forward… 6…7.
So, 5 + 2 = 7
Counting back from a number is the same as subtracting from that number.
o Start with the first number and count back the amount of the second number, tracking the
change using a math tool or fingers.
o A common mistake is to include the starting number when counting on or back.
 For example, 11 - 2 = 10, instead of counting jumps the child includes the original
number (11, 10…student is counting 2 numbers rather than 2 jumps). To help with this,
students can point to the starting number and whisper it, then count on or back by
saying the numbers out loud.

These strategies are most efficient when used to add or subtract the numbers 1, 2, or 3. Students use
math tools, number lines, and hundreds charts to help them count on and count back.
Making a ten to add and subtract
o This strategy is based on the concept of ten and the understanding that numbers from 11 to 20 can
be expressed as ten and some more.
o A tool called a ten frame helps children keep track when counting 10 or more.
 The ten frame visually shows two rows of 5. Counters are placed from
left to right in each row to reinforce one-to-one correspondence.
 This example shows one group of 10 and 2 more to represent the
number 12.
o Decomposing (or breaking apart) numbers allows students to simplify addition and subtraction by
making a ten and then adding or subtracting the remaining amount.
Break apart the 3 into 2 and 1, then add 8 + 2
to make a 10. Finally, add 10 + 1 to get 11.
14 – 5
Break apart 5 into 4 and 1. Subtract 14 – 4 to
make a 10. Then, subtract 10 – 1 to get 9.
Check out the “Parent Quick Smarts” video by
scanning the QR code or the Internet link
provided.
Other Helpful Links:
http://goo.gl/gBKR6p - Interactive number line
http://goo.gl/nrguau - Interactive math tools - counters
(ten frame icon at bottom left of page)
http://www.mathplayground.com/number_bonds_10.html Making ten game
http://goo.gl/sgThny - Animated Lessons
 Skill 13: Count on to Add
 Skill 17: Make a Ten to Add
 Skill 19: Count Back to Subtract Facts to 12
https://www.youtube.com/watch?v=SIl2JqgzT
http://goo.gl/Hk5wqc - Addition/Subtraction games:
Numberopolis, Cross Town Number Line
 H. 0-20: Count on to Add
 I. 0-20: Count Back to Subtract
Country Countdown, Counting Critters
 Q. Make 10 to Add
Sample tasks your child should be able to work through by the end of the unit:
Use the ten frame to show how to make a
ten and add.
Allison had 5 peppermints and gave 2 to Brandon.
How many peppermints does Allison have now?
Tell which strategy you used and why.
8 + 3 = ______
Count back. Write the difference.
6 – 3 = ______
Purposeful Practice you and your child may work on at home together.

Pose real-world story problems that deal with adding/subtracting 1, 2 or 3. Have your child model the
actions on a number line, using objects (such as beans, toothpicks, cereal, pennies, etc.), or by counting
aloud using his/her fingers.

Give your child a handful of something (marbles, cotton balls,
etc.) and ask him/her to separate them into a group of 10 and
some more.
Use an empty egg carton as a ten frame by cutting off two of the
egg spaces. Pose addition or subtraction problems for your
child to solve using the modified egg carton and some small
objects as tools. Make sure the problems include one number
between 10 and 20.

Hillsborough County Public Schools
Elementary Mathematics Parent Connection
Grade 1 – Think Addition to Subtract
In this unit your child will work to build an understanding of using addition facts to solve subtraction problems
and subtracting to compare two amounts.

Using addition facts to subtract
o
Students will explore the concept of missing addends (numbers being added) by utilizing addition facts
they already know to solve a related subtraction problem.
Examples:
Solve 9 – 4
Think
Solve
Think
4+?=9
Since 4 + 5 = 9
Then, 9 – 4 = 5
o

12
- 7
?
7
+ ?
12
I know…
7
+5
12
So,
12
- 7
5
Students should realize that the 3 numbers in the addition fact are the same 3 numbers used in the
subtraction fact and that the difference (answer) to the subtraction fact is the missing addend in the
addition fact.
Subtracting to compare
o
As students model compare situations they will see that an amount is not being “taken away,” as in
previous subtraction experiences. Since the two quantities are separate from each other and not part of
a whole, they will both be represented and then compared to find how many fewer or how many more.
Example:
There are 6 children and 4 hats. How many more hats are
needed so that each child gets a hat?
6–4=?
Since 2 people are left
without a hat, 2 more hats
are needed. So, 6 – 4 = 2
Children are encouraged to draw a picture or use math tools, lining
up each object to show one-to-one correspondence.
o A bar model may also be used to represent comparison problems.
Jill has 8 stickers.
She has 5 more
stickers than Derek.
How many stickers
does Derek have?
One bar is drawn to represent the greater
quantity. A shorter bar is drawn to represent
the smaller quantity. The distance from the
end of the shorter bar to the end other
longer bar represents the difference in
quantities.
Check out the “Parent Quick Smarts” video by
scanning the QR code or the Internet link
provided.
Other Helpful Links:
http://goo.gl/nrguau - Interactive math tools counters
http://goo.gl/sgThny - Animated Lessons
 Skill 9: Subtract to Compare
 Skill 20: Think Addition to Subtract
https://www.youtube.com/watch?v=SIl2JqgzT
FQ
http://goo.gl/Hk5wqc - Addition/Subtraction Games
Numberopolis, Carnival Stories
 O. Comparison Stories to 20
 N. Missing Addends to 20
Sample tasks your child should be able to work through by the end of the unit:
Mark finds the difference of 15 – 6. Write a
related addition sentence that Mark can use to
check his answer.
Which addition sentence
helps you solve 11 – 8?
A.) 3 + 5 = 8
B.) 5 + 6 = 11
C.) 8 + 3 = 11
D.) 8 + 4 = 11
There are 4 red cups. There are 3 more red
cups than yellow cups. How many cups are
yellow?
Draw a model to show your thinking. Write a
number sentence to represent your model.
Shawn’s shirt has 5 buttons and
Angie’s shirt has 2 buttons. How
many fewer buttons does Angie’s
shirt have than Shawn’s?
Purposeful Practice you and your child may work on at home together.

Give your child three related numbers (such as 3, 5, 8 or 4, 9, 13) and ask him/her to write two addition facts and
two subtraction facts using only those numbers.

Play a game using half of a plastic egg and some sort of small objects like beans. Put
some beans on the table and have your child count them. Then, asking your child to
close his/her eyes, hide some of the beans under the egg. Have him/her write an
addition and a subtraction problem to match what happened.

Pose real-world comparison problems for your child to solve. Allow him/her to use
tools (such as beans, dried pasta, raisins, pennies, etc.) or to draw pictures to solve
the problems if needed.
Here are some example problems you could use:
o “There are 8 apples and 6 bananas. How many more apples are there?”
o “There are 12 chairs and 15 desks. How many fewer chairs are there?”
o “There are 14 big shells. There are 5 more big shells than small shells. How many small shells are there?”