My Math, Grade 1 © 2013 / 2014
Chapter 3: Addition Strategies to 20
Lesson 5: Use Near Doubles to Add
What's the Math?
Common Core State Standards
FOCUS
Domain: Operations and Algebraic Thinking
Major Cluster: Add and subtract within 20.
Objective: Students will use the near doubles to add strategy to help find the sum.
Standards
1.OA.6Add and subtract within 20, demonstrating fluency for addition and
subtraction within 10. Use strategies such as counting on; making ten;
decomposing a number leading to a ten; using the relationship between
addition and subtraction; and creating equivalent but easier or known sums.
Mathematical Practices
1 Make sense of problems and persevere in solving them.
2 Reason abstractly and quantitatively.
3 Construct viable arguments and critique the reasoning of others.
4 Model with mathematics.
5 Use appropriate tools strategically.
6 Attend to precision.
7 Look for and make use of structure.
COHERENCE
Thinking Across Grades
Previous
Now
Next
Grade K K.OA.5
Grade 1 1.OA.6
Grade 2 2.OA.2
Linking to Major Topics
Connected to the following critical area of focus: 1. Developing understanding
of addition, subtraction, and strategies for addition and subtraction within 20.
Connected to the following standards: K.OA.2, K.NBT.1, 1.OA.5, 2.OA.2
RIGOR
The exercises increase in complexity throughout the lesson.
However, individual student thinking may vary during extended processing.
Levels of Complexity
Level 1 Understand Concepts Exercises 1–2
Level 2 Apply Concepts Exercises 3–17
Level 3 Extend Concepts Exercises 18–19; HOT Problem
What Students Should Understand
Near doubles are doubles facts that are plus or minus one.
What Students Should Be Able To Do
Students should be able to add doubles and add one or subtract one to find a near double fact.
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My Math, Grade 1 © 2013 / 2014
Chapter 3: Addition Strategies to 20
Lesson 5: Use Near Doubles to Add
3
3
+
3
+
=
4
6
=
7
Building on the Essential Question
In this lesson, students will build upon the skills and concepts needed to answer the chapter’s Essential
Question “How do I use strategies to add numbers?”
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My Math, Grade 1 © 2013 / 2014
Chapter 3: Addition Strategies to 20
Lesson 5: Use Near Doubles to Add
Developing Vocabulary / Get Ready
New Vocabulary/Cognate
doubles/dobles
doubles minus 1
doubles plus 1
Activity
Have students tell what they know about doubles and using
doubles to add.
Model with Mathematics Have students work in pairs. Have each pair use cubes to show an
example of a doubles fact. Then have the pair write the addition number sentence that describes their
model.
Review the meaning of plus and minus and discuss what it means
to have doubles plus 1 and doubles minus 1 facts.
English Language Learner Instructional Strategy
Collaborative Support: Think-Pair-Share
Before Explore and Explain, model adding the doubles fact, 3 + 3 = 6,
with connecting cubes. Ask, What is the sum? six Write 3 + 3 = 6.
Display two groups of 3 connecting cubes. Say, Here are two groups of
three. I will remove one cube. Remove 1 connecting cube from a group
of 3, to make 2. Hold up the group of 2 and ask, How does this group
differ from the other? It has one less cube. Hold up both groups and say,
I removed one cube from the group, so together they have one less than
three and three. The sum of 3 + 2 will be one less than the sum of 3 + 3.
Write 3 + 2 = ?. Ask, What is one less than the sum of three plus three?
five Complete the number sentence by writing the sum, 5. Repeat
modeling adding one more to 3 + 3 = 6 to have 3 + 4 = 7.
Have students work in pairs using near doubles to solve Exercises 3–17.
Have pairs share their findings with another pair or the whole group.
For non-Spanish speaking ELLs, refer to the Multilingual eGlossary for
interactive definitions in 13 languages.
My Vocabulary Cards
Ask students to create categories for the vocabulary cards in this chapter.
Virtual Word Wall
You may wish to add the vocabulary words doubles, doubles minus 1, and doubles plus 1 to the Virtual
Word Wall for the chapter.
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My Math, Grade 1 © 2013 / 2014
Chapter 3: Addition Strategies to 20
Lesson 5: Use Near Doubles to Add
Launch the Lesson / Investigate & Model
Review
Problem of the Day
Use the part-part-whole mat to show how to solve this problem. There
were 10 birds in a tree. Some flew away and 2 remained. How many
birds flew away? 8 birds
Use Appropriate Tools Have students explain how they used
the part-part-whole mat to solve the problem of the day. Which
number is the whole? 10 Which number is the known part? 2 How did you
solve for the missing part? Sample answer: I modeled 10 counters and
then I took away 2 to find the answer, 8.
Common Core Quick Check
Use this activity as a quick review and assessment of the
previous lesson. A printable version is available online.
Additional review occurs at the end of the chapter.
Additional Resources
Literature Connection
Read a trade book, such as Double Play by Betsy Franco, to prepare
students for this lesson.
Investigate the Math
Target: Procedural Skill and Fluency
Materials: red and purple connecting cubes
This investigation emphasizes mathematical reasoning and
mathematical processing.
How can you use near doubles to add?
Students investigate ways to model with math.
Students come together to discuss their results and reason abstractly.
Model the Math
Target: Procedural Skill and Fluency
Materials: red and purple connecting cubes, write-on/wipe-off board, dry erase markers
You will need: red and purple connecting cubes
Hold up cube trains of five red connecting cubes and five purple connecting cubes. Join the trains as
students watch.
What is the addition number sentence? 5 + 5 = 10
Separate the trains and add one more red cube to the red train. Join the trains again. Explain to
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My Math, Grade 1 © 2013 / 2014
Chapter 3: Addition Strategies to 20
Lesson 5: Use Near Doubles to Add
students this is a doubles plus one fact.
What is the addition number sentence? 5 + 6 = 11
Have students show the original doubles fact. Tell students to take away one cube. Explain to students
that this is a doubles minus 1 fact.
What is the addition number sentence? 5 + 4 = 9
Have students work with a partner. Tell students that one partner uses cubes to show a doubles fact
and the other partner makes it a doubles plus 1 fact. Have students switch roles. Then have one
partner use cubes to show a doubles fact while the other partner makes it a doubles minus 1 fact. Have
students switch roles again. Have students show their cube trains to the class. Have the class say the
sum of each of the trains presented.
Resources
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My Math, Grade 1 © 2013 / 2014
Chapter 3: Addition Strategies to 20
Lesson 5: Use Near Doubles to Add
Teach
Explore and Explain
You will need
connecting cubes
Read the directions at the bottom of the student page.
Create two groups of connecting cubes with three cubes in each group. Now add one cube to one
of the groups or take away one cube from one of the groups. Trace the cubes.
How do the groups of cubes differ from each other? Sample answer: One group has one more
cube than the other group.
Lead students through the steps needed to write and solve their addition number sentences using the
near doubles strategy.
When you have two addends that are nearly the same, you can use the near doubles strategy to
find the answer. For example, if you need to add four and five, you know that four plus four equals
eight. Four plus five is one more, so you can count on one more from eight to get the answer,
which is nine.
Could you also find the answer by adding five and five? Explain. Sample answer: Yes; You know
that five and five is ten. Four and five is one less, so you count back one from ten to get nine.
Construct Arguments Why do you suppose near doubles facts
are called this? Sample answer: They are close, or near, to being the same
as double facts. They are only different by 1 number.
See and Show
Guide students through the example at the top of the student page. Read the sentences to the class.
Provide each student with one yellow and 10 green connecting cubes. Have students model each
example shown using connecting cubes while you explain the differences between the doubles and
near doubles facts. Tell students to trace the dashed numbers that represent the sums of each of the
facts.
Reason Quantitatively Have students look at the example
about doubles minus 1. Ask: Is there a doubles plus 1 fact you could use
to solve 5 + 4? Help students realize that the doubles fact 4 + 4 could
also help them solve 5 + 4.
Work through Exercises 1–2 as a class.
Talk Math: Collaborative Conversation
Discuss with students “How do doubles facts help you learn near
doubles facts?” Sample answer: You can find doubles, then you can
add 1 or subtract 1.
Use Structure Have students explain to a partner when it is a
good idea to use the near doubles strategy to add.
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My Math, Grade 1 © 2013 / 2014
Chapter 3: Addition Strategies to 20
Lesson 5: Use Near Doubles to Add
Practice & Apply
On My Own
Based on your observations, you may choose to assign exercises
as noted in the levels below:
Approaching Level Guide students through the exercises in On My Own. Help them to use
manipulatives.
On Level Have students complete the exercises independently.
Beyond Level Have students complete the exercises independently without manipulatives.
Common Error! Some students will recognize a near doubles problem but may have difficulty keeping
two steps in their head at the same time. It might be helpful for them to write the doubles fact above the
near doubles fact until the doubles facts become automatic.
Problem Solving
Persevere in Solving Problems
Exercise 19 Ask: Is counting on a good strategy to use to solve this exercise?
Why or why not? Sample answer: No because I have to count on 8, which
takes more time than using doubles plus or minus 1 would take.
Attend to Precision
HOT Problem Have students identify which numbers are the addends
and which number is the sum in this exercise. Students should explain
their reasoning.
Formative Assessment
Reflections Have students write a doubles fact of their choice. Then
have them write a near doubles fact and solve. Ask students to
explain their choices.
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My Math, Grade 1 © 2013 / 2014
Chapter 3: Addition Strategies to 20
Lesson 5: Use Near Doubles to Add
Differentiated Instruction
Differentiated Instruction
TIER 2: Strategic Intervention
Hands-On Activity Materials: two-color counters
Give students six counters. Tell students to
show three yellow counters and three red
counters. Ask students what doubles fact they
can make. 3 + 3 = 6 Give students one more
counter and have students place it yellow side
up. What is your new addition number sentence?
3 + 4 = 7 How did one of the addends change?
It increased by 1. How did the sum change? It
increased by 1. Continue making other
doubles, doubles plus 1 facts, and doubles
minus 1 facts. Have students identify the
changes that occur in forming each doubles
plus 1 or doubles minus 1 facts.
TIER 1
Hands-On Activity Materials: index cards, pencils
Have students write a doubles fact and the
related doubles plus one fact on an index card.
Have students create 8 sets of cards. Then have
students shuffle the cards and lay them
facedown. Have students take turns turning
over two cards at a time. If the cards show a
doubles fact and the related doubles plus one
fact, students keep the cards and get another
turn. Play continues until all matches have
been found.
Extend
Hands-On Activity Materials: number cards
for 3, 5, 7, 9, 11, 13, 15, and 17; connecting
cubes
Have students choose a card. Have them use
connecting cubes to show a doubles plus 1
fact that has the sum of the number on the
card. Then have them use connecting cubes to
show a doubles minus one fact that has the
sum. Have students choose a new card and
repeat the activity.
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My Math, Grade 1 © 2013 / 2014
Chapter 3: Addition Strategies to 20
Lesson 5: Use Near Doubles to Add
Differentiated English Language Learner Support
Number Sense
Distribute one color of connecting cubes.
Write 2 + 2 = 4. Have students model the
sentence and say, Two plus two equals four.
Ask, Are the addends doubles? yes Students
should nod or show thumbs-up. Give each
student one different color connecting cube.
Have students place the different color cube
on one of their trains. Ask, What is two plus two
and one more? Encourage students to say with
you, Two plus two is four. Four plus one is five.
Repeat with other sets of doubles.
Number Recognition
Distribute 10 counters to each pair of students.
Have one student place 3 color counters in
each hand. Have student B write and say the
number sentence: 3 + 3 = 6. Say, doubles plus
one, and distribute one different color counter
to each pair. Have student B place the counter
in one of student A’s hands. Have student B
write “+ 1 = 7” after the number sentence
and say: 3 + 3 + 1 = 7. Have partners switch
roles and repeat the activity with different
doubles facts minus 1.
Making Connections
Provide pictures or show realia (concrete
objects) of different sets of doubles. For
example, show two packs of five pencils. Have
students suggest other items that come in
multipacks of two, three, four, five, or six that
can represent doubles. For each example, ask,
How many would you have if you had one more/
one less? Have students find the sum of the
doubles and then add or subtract one and
explain using the words doubles plus one or
doubles minus one.
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My Math, Grade 1 © 2013 / 2014
Chapter 3: Addition Strategies to 20
Lesson 5: Use Near Doubles to Add
Wrap It Up
My Homework
Assign homework after succesful completion of the lesson. Students who understand the concepts may
skip the Homework Helper section.
Problem Solving
Exercise 9 Purposely present an incorrect answer to this exercise
and ask students to find the error. For example, tell students that you
think the answer to this problem is 1. Have students work together in
small groups to find and analzye your error. Invite students to explain
what you might have done wrong and help you reach the correct
answer.
Vocabulary Check
Prompt students to compare the two facts shown in Exercise 10 to help
them find the correct answer.
Formative Assessment
You will need
• write-on/wipe-off boards
• dry-erase markers
Response Cards Ask students the following questions and have them
write their answers on a write-on/wipe-off board. Have students hold
up their boards to display their answers.
Which doubles fact could help you solve 5 + 4?
Sample answer: 5 + 5
Which doubles fact could help you solve 7+ 8?
Sample answer: 7 + 7
Write an example of a near doubles fact.
Sample answer: 6 + 7
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My Math, Grade 1 © 2013 / 2014
Chapter 3: Addition Strategies to 20
Lesson 5: Use Near Doubles to Add
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