Math Fact Strategy Seed Ideas
Addition and Subtraction
(based on Teaching Student-Centered Mathematics, 2006)
Near Doubles Strategy
The “near doubles” strategy is used when the two addends in the number sentence are close to
being the same (1 or 2 apart), hence the near doubles. Extensive practice with visualizing
numbers as dot and other pictorial representation is especially helpful with this strategy, so
that students can apply their understanding of the doubles strategy and counting on strategy.
Students should use the commutative property to be able to apply this strategy to twice as
many facts. When the addends are “two apart”, students can double the middle number.
Seed Idea: Near Doubles Strategy Cards
 Addition: Fold the card over on the dotted line so the doubles fact is showing. Ask the
students what doubles fact is showing. Then ask them how the sum would change if one
of the addends was just one more. Fold on the other flap to show them the doubles +1
fact.
 Subtraction: Lay the card flat so that all three pictures are shown. Give them a sum and
ask them to find which two pictures have that many dots. Then, have them tell the
doubles or near doubles subtraction sentence that they found.
Seed Idea: Near Doubles Turn around Cards
 Addition: Show the turn around card to students and have them tell you the number
sentence that it represents. (8+9=17) Then, turn around the card and tell the number
sentence that is represents (9+8=17)
 Subtraction: Take the card and write the sum on the back. Have students decompose
that number as many ways as possible and circle which one of the ways they decomposed
the number is a near doubles fact. Flip the card over to check.
Seed Idea: Near Doubles Flashcards
 Addition: Show the flashcard and have them use the near doubles strategy to solve the
fact. This should only be used after extensive work with the meaning of operation and
application of the strategy.
Seed Idea: Near Doubles Folding Cards
 Addition: Fold the cards on each of the dotted lines and glue the black domino card so
that it is on the back. Have the students look at the doubles picture and tell you what
number sentence is represented. Then fold the black domino card over top and have
them tell you what number sentence is represented now.
 Subtraction: Give them a sum and ask them to find which two pictures have that many
dots. Then, have them tell the doubles or near doubles subtraction sentence that they
found.
Seed Idea: Near Doubles Subtraction Flashcards
 Subtraction: Cut out the flashcards and then fold them on the dotted line. Show the
flashcard and have them use the near doubles strategy to solve the fact. This should
only be used after extensive work with the meaning of operation and application of the
strategy. Discuss what matching think-addition number sentence can be created from
the subtraction number sentence. Also, have them tell you which two numbers in the
number sentence are the near doubles numbers,
Seed Idea: Near Doubles Missing Addend Cards
 Addition: Cut out the flashcards and then fold them on the dotted line. Show them the
missing addend card and have them figure out what the missing addend would be. Have
them share what strategy they used to find the missing addend.
 Subtraction: Have them determine the missing addend and tell what the related
subtraction fact would be.
Seed Idea: Near Doubles Think Addition Cards
 Addition: Cover the bottom number and ask the students what the total number of dots
would be. Discuss what strategies were used to find the answer.
 Subtraction: Fold down one of the addends and ask them how many dots are missing.
Have the students share the strategies that they used to determine the missing number
of dots.
Seed Ideas: Near Doubles Pictures
 Addition: Take a piece of paper and fold it in half and have the students put small blobs
of tempra paint on the left side of the paper and then fold it over while the paint is still
wet. Then, have them add one or two more blobs on the right side to represent a near
doubles fact. Write the fact.
 Subtraction: Give them a near doubles sum, like 13 and have them put the same amount
of blobs on each side of the paper and one or two more on one side to represent the near
doubles fact. Have them write the subtraction fact (13-6=7) that is represented. Make
the connection to fair share and division.