Addition and Subtraction Strategies
The ultimate goal of the Common Core Curriculum is for students to be able to fluently solve addition
and subtraction problems using mental math or a strategy involving place value. By the end of 2nd grade
students should be able to use a strategy they know to solve a problem, but most importantly, explain
what they did and why it makes sense. We hope the strategies below will help you support your child as
he/she progresses from the pictorial representation to a strategy that utilizes numbers and an
understanding of place value.
Models
Addition
Subtraction
1. Draw one number as 10s and 1s
1. Draw the LARGEST number as 10s and 1s
2. Draw the other number as 10s and 1s
3. Add all the 10s and 1s, order does not matter
*Sometimes you will need to compose a 10 or a
100
4. Add the total of 100s, 10s, and 1s to find answer
2. CROSS OUT the second number as 10s and 1s
*Sometimes you will need to decompose a 10 to
get ten more 1s
3. Add the remaining 10s, and 1s to find the answer
Number-Line
Addition
1. Draw a line
2. Choose one number to start with, write it on the
LEFT side
3. Count on the amount of the second number: Use
jumps of 10s and 1s, order doesn't matter
Subtraction
1. Draw a line
2. Must start with LARGEST number and write it on
the RIGHT side
3. Count back the amount of the second number:
Use jumps of 10s and 1s, order doesn't matter
Addition
Break-Apart Strategy #1
Subtraction
1. Write one number in expanded notation
1. Write the LARGEST number in expanded form
2. Write the other number in expanded notation
2. Write the other number in expanded form
3. Add the 10s to find total of 10s
3. Subtract the 10s
4. Add the 1s to find total of 1s
4. Subtract 1s *Sometimes you may need to decompose a
10 to get more ones
5. Use a new number sentence to find the total of 10s and
5. ADD the remaining 10s and 1s to find the answer.
1s.
Addition
Break-Apart Strategy #2:
Subtraction
1. Start with the whole first number.
1. Start with the whole first number.
2. Add the 10s from the second number to the first
number.
2. Subtract the 10s of the second number from the first
number.
3. Add the 1s from the second number to the previous
3. Subtract the 1s from the previous difference.
sum.
Addition
Break-Apart Strategy #3:
Subtraction
1. Add 10s from both numbers to find the total of 10s
2. Add 1s from both numbers to find the total of 1s
3. Add the total of 10s and total of 1s to find the answer
1. Subtract 10s from both numbers to find the remaining
10s
2. Subtract 1s from both numbers to find the remaining 1s
*Sometimes you may need to decompose a 10 to get
more ones
3. ADD the remaining 10s and 1s to find the answer