Facts Using Doubles
Objective To provide opportunities for children to explore and
practice doubles-plus-1 and doubles-plus-2 facts, as well as
review strategies for solving other addition facts.
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Teaching the Lesson
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Assessment
Management
Common
Core State
Standards
Ongoing Learning & Practice
Key Concepts and Skills
Guessing the Grab
• Develop and practice strategies for addition
that use doubles facts.
clear plastic bag pattern blocks paper bag (optional)
Children describe the probability of
grabbing a given shape from a clear
bag containing different shapes.
[Operations and Computation Goal 1]
• Use a variety of addition fact strategies for
solving multi-addend addition problems.
[Operations and Computation Goals 1 and 2]
Key Activities
Children identify and practice strategies that
use doubles facts. They also practice adding
3 or more addends and discussing the
strategies they use.
Ongoing Assessment:
Recognizing Student Achievement
Math Boxes 5 10
Math Journal 1, p. 99
Children practice and maintain skills
through Math Box problems.
Home Link 5 10
Math Masters, p. 149
Children practice and maintain skills
through Home Link activities.
Curriculum
Focal Points
Interactive
Teacher’s
Lesson Guide
Differentiation Options
READINESS
Exploring Doubles
number cards 0–10 (from Math Journal 1,
Activity Sheet 1; or the Everything Math
Deck, if available)
counters
Children practice with doubles facts using
counters.
EXTRA PRACTICE
Playing Domino Top-It
dominoes
Children practice comparing quantities and
finding sums.
Use Mental Math and Reflexes. [Operations and Computation Goal 4]
Key Vocabulary
doubles-plus-1 fact doubles-plus-2 fact
Materials
Math Journal 1, p. 98
Home Link 59
counters of two colors or types 3 or 4 dice
Advance Preparation
Teacher’s Reference Manual, Grades 1–3 pp. 196–198
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Place Value, Number Stories, and Basic Facts
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Getting Started
Mental Math and Reflexes
Math Message
Tell simple number stories. Children use any strategy to solve them and then
share their solution strategies. Summarize solutions with an appropriate diagram
and number model. (Remember not to force the solution to a number story into a
particular mold.) If children are able to do so, ask them to complete the diagrams and/or
suggest a number model. Children should not be expected to do either at this time.
Write 5 doubles facts that
you are sure about.
Number story suggestions:
Home Link 5 9
Follow-Up
Malcolm has 7 basketballs and 7 baseballs. How many balls does Malcolm
have in all? 14 balls; 7 + 7 = 14
Henrietta had 15¢. She gave the cashier 5¢ for an eraser. How much money
does Henrietta have left? 10¢; 15 - 5 = 10
Briefly go over the
answers.
Raymond and Eli collect baseball cards. Raymond has 19 cards. Eli has fewer
cards than Raymond. The difference between the number of cards that Raymond
has and the number of cards Eli has is 10. How many cards does Eli have in all?
9 cards; 19 – 9 = 10
Mental Math
Ongoing Assessment:
and Reflexes
Recognizing Student Achievement
Use Mental Math and Reflexes to assess children’s ability to solve simple
number stories. Children are making adequate progress if they are able to
correctly answer the first problem. Some children might answer all three
problems with relative ease.
[Operations and Computation Goal 4]
1 Teaching the Lesson
Math Message Follow-Up
WHOLE-CLASS
DISCUSSION
Ask children to name the doubles facts they know. List doubles
facts in a column on one side of the board until you have listed all
of the facts from 1 + 1 = 2 through 10 + 10 = 20. Leave enough
space between each doubles fact to write an additional fact later
in the activity. Ask: What do all doubles facts have in common?
Sample answers: Both addends are the same; the sums are all
even. Tell them that today they will learn how to use doubles facts
to solve other facts.
Introducing
WHOLE-CLASS
ACTIVITY
Doubles-Plus-1 Facts
Without erasing the doubles facts you listed on the board for the
Math Message Follow-Up, focus children’s attention on 5 + 5 = 10.
Have children use one color or type of counters to show two
columns of 5 counters each. Represent this on the board with a
drawing labeled 5 + 5 = 10.
5 + 5 = 10
Lesson 5 10
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5 + 5 = 10
5 + 6 = 11
NOTE Knowledge of doubles facts is
important, as this lesson focuses on strategies
that assume quick recall of these facts. Daily
practice of the doubles facts will help reinforce
this skill.
NOTE Be sure to add Doubles-Plus-1
and Doubles-Plus-2 strategies to your Fact
Strategy Wall.
Have children add one counter of a different color or type to the
top of one column. Represent this on the board by drawing a
counter of a different color on top of the right column. Ask: How
is this like 5 + 5 = 10? How is it different from 5 + 5 = 10?
Sample answer: It still has two sets of 5 counters, but it has
1 extra counter in one of the columns. Below the drawing, write
the number model 5 + 6 = 10. Ask: Is this number model true or
false? false Erase the 10. How could you use doubles to solve
this problem? You can add 5 + 5 = 10 and then add one more
to make 11. Write 11 to the right of the equals sign. Ask: Is this
number model true or false? true Explain that this is called a
doubles-plus-1 fact.
Repeat this activity with several other doubles-plus-1 facts. Then
ask children to look at the list of doubles facts on the board and
name some doubles-plus-1 facts that could be solved using the
doubles facts. Insert these doubles-plus-1 facts next to the doubles
facts in your list of facts. Point to various facts and ask how
children could use doubles facts to find the sums. Once children
seem to grasp the strategy, ask them to describe the strategy to
put on the Fact Strategy Wall. For example, for the fact 3 + 4,
children might say: You know that 3 + 3 = 6. Since 4 is one more
than 3, then 3 + 4 is one more than 3 + 3. So to solve 3 + 4, you
can think of the problem this way:
3+3=6
and 6 + 1 = 7
so 3 + 4 = 7.
Introducing
WHOLE-CLASS
ACTIVITY
Doubles-Plus-2 Facts
Begin again with the doubles fact 5 + 5 = 10 written on the board
and represented by two columns of 5 counters of the same color
or type. Have children make two columns of 5 counters. Have
children add two counters of a different color or type to one
column. Draw two different counters at the top of one of your
columns. Change the number model to 5 + 7 = 10. Ask: Is this
number model true or false? false Erase the 10. Ask: How can we
use the doubles fact 5 + 5 = 10 to solve this problem? Since
5 + 5 = 10 and there are 2 extra counters, add 2 to 10. Since
10 + 2 = 12, then 5 + 7 = 12. Explain that this is called a
doubles-plus-2 fact. Write 12 to the right of the equals sign.
Ask: Is this number model true or false? true
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Student Page
Ask: Can anyone think of another doubles fact that can be used to
solve this problem? This will likely be a difficult question for children
to answer. Guide children by moving one of the counters from the
taller column to the shorter column. Again ask: Can anyone think of
another doubles fact that can be used to solve this problem? Children
should now be able to see that 5 + 7 = 6 + 6 = 12.
Have children use counters to practice using both methods to solve
a variety of doubles-plus-2 facts. Some children will find that one
method is easier for them than the other.
Date
LESSON
5 10
Using Doubles Facts
Add. Use doubles facts to help you.
1. 5 + 4 =
9
2.
15
=8+7
3. 3 + 4 =
7
=7+9
7. 6 + 4 =
10
4. Explain how you solved 3 + 4.
Answers vary.
5. 5 + 3 =
8
6.
16
8. Explain how you solved 6 + 4.
Answers vary.
Practicing Using Doubles
INDEPENDENT
ACTIVITY
to Add
(Math Journal 1, p. 98)
In Problems 1–3, children solve problems that could be solved
using the doubles-plus-1 strategy. In Problems 5–7, they solve
problems that could be solved using the doubles-plus-2
strategies. Take care, however, not to force a particular strategy
for a problem. Your most efficient strategy for solving a particular
problem may not be the most efficient strategy for every child.
Demonstrating a variety of strategies and allowing children to
share and discuss their own strategies with the class will allow
children to internalize the strategies that are most efficient for
them over time. Problems 4 and 8 will give insight into what
strategies children are using most comfortably.
Doing a Dice-Roll
Math Journal 1, p. 98
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WHOLE-CLASS
ACTIVITY
Activity
Ask a child to roll the dice and say aloud the numbers shown.
Write the numbers on the board as an addition number model
with an answer box for the sum. Have another child describe
one strategy for adding the numbers. Show the order in which
the child adds the numbers by connecting pairs of numbers and
writing their sum. Write the sum of the numbers in the answer
box. Refer to the Fact Strategy Wall as strategies arise (doubles,
doubles-plus-1, doubles-plus-2, making ten, +10, etc.). Write the
number model again and ask other children to add in a different
order while you note the steps, the strategies used, and the sum.
4 + 3 + 6 + 4 = 17
7
+
10
17
You may wish to use this activity as an ongoing routine to practice
fact strategies. As your class becomes more comfortable, try these
variations: roll additional dice, roll again when a 1 appears on
a die, or include one or more polyhedral die (8–20 sides). Have
partnerships or individuals roll dice and record their work on
slates or on paper.
Lesson 5 10
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2 Ongoing Learning & Practice
Guessing the Grab
WHOLE-CLASS
ACTIVITY
Display a large, clear plastic bag containing 3 orange squares and
5 green triangles. Explain that you are going to close your eyes,
reach into the bag, and grab a shape. Ask them which shape they
think you will likely grab. Allow them to explain their reasoning.
Then grab and remove a shape. Children continue to make
predictions about what shape you will remove. Continue to remove
shapes from the bag until the bag is empty. Refill the bag with
different shapes. Repeat the activity.
After doing this activity several times, discuss children’s
observations. For example:
●
The shape with the greatest quantity is likely to be grabbed.
●
The shape with the least quantity is unlikely to be grabbed.
●
As you remove shapes from the original bag, the likelihood of
which shape you grab will change.
Adjusting the Activity
When children start to see patterns in probability, do this activity with a
brown paper bag. Show children what shapes and how many of each shape are
in the bag. Then ask them which shape they think you are most likely to remove.
Continue the activity as described.
A U D I T O R Y
K I N E S T H E T I C
T A C T I L E
V I S U A L
Links to the Future
“Guessing the Grab” gives children the opportunity to use the most basic
language of probability. They will be exposed to this language throughout the
year. Explaining the most basic language of probability is a Grade 2 Goal.
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Student Page
Math Boxes 5 10
Date
INDEPENDENT
ACTIVITY
LESSON
Math Boxes
5 10
1. Draw and solve.
(Math Journal 1, p. 99)
2. Add.
Jade has 5 pennies.
5+6=
Max has 9 pennies.
Mixed Practice Math Boxes in this lesson are paired
with Math Boxes in Lesson 5-12. The skills in Problem 4
preview Unit 6 content.
15
How many fewer pennies?
Home Link 5 10
4
7
+5
6
+8
12
14
fewer pennies
Sample answer:
INDEPENDENT
ACTIVITY
(Math Masters, p. 149)
=7+8
Who has fewer pennies?
Jade
11
3. Record the temperature.
4. Count up by 5s.
°F
80
Home Connection Children find the sums of near-doubles
addition facts and solve base-10 block riddles.
25,
70
60
30
,
35
,
,
50
,
40
,
45
55
,
60
50
40
64
°F
3 Differentiation Options
Math Journal 1, p. 99
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READINESS
Exploring Doubles
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PARTNER
ACTIVITY
5–15 Min
(Math Journal 1, Activity Sheet 1)
NOTE Remember to reserve time every day
to complete the number-line, attendance,
calendar, weather, and temperature routines.
To explore doubles using a concrete model, have children model
doubles facts using counters. Children mix up number cards and
place them in a deck facedown. One child selects a number card
and uses that number of counters to make a row. The other child
uses the same number of counters to make a row beside the first
row. Children each write the doubles fact represented by the
counters on a sheet of paper. They draw a picture to go with their
doubles fact. Children repeat this activity as time allows.
Home Link Master
Name
Date
HOME LINK
5 10
Family
Note
Using Doubles Facts
Today children used doubles facts to solve other addition facts. For example, if children know
that 5 + 5 = 10, then they can use that to solve 5 + 6 by solving 5 + 5 and adding 1 more.
So 5 + 6 = 11. We call these “doubles-plus-1 facts.” Children also learned doubles-plus-2
facts, such as 6 + 8. By adding 1 to the larger addend and subtracting 1 from the smaller
addend, children can use 7 + 7 = 14 to solve 6 + 8 = 14. Doubles-plus-2 facts can also
be solved by doubling the smaller number and adding 2 more. Review doubles-plus-1 and
doubles-plus-2 facts with your child.
Please return this Home Link to school tomorrow.
Write the sums. Tell someone at home how you can
use doubles facts to solve the problems.
1. 3 + 4 =
4.
7
17
2.
5.
8
+7
15
3. 7 + 5 =
=8+9
6.
5
+3
8
7.
4
+6
10
12
6
+5
11
Practice
Solve the riddles.
8. 2
and 4
=
24
9. 4
and 7
=
47
Math Masters, p. 149
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Lesson 5 10
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EXTRA PRACTICE
Playing Domino Top-It
PARTNER
ACTIVITY
15–30 Min
Children determine sums and compare quantities by playing
Domino Top-It.
Directions
1. Children place the dominoes facedown on the table.
2. Each child chooses a domino and compares the total number
of dots to the total number on his or her partner’s domino.
3. The child with the larger total takes both dominoes. Ties
are settled by another draw.
4. The game ends when time is up or when all of the dominoes
have been drawn.
Planning Ahead
Provide time for children to work on the number scrolls that they
began in Lesson 4-10.
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Name
HOME LINK
5 10
Family
Note
Date
Using Doubles Facts
Today children used doubles facts to solve other addition facts. For example, if children know
that 5 + 5 = 10, then they can use that to solve 5 + 6 by solving 5 + 5 and adding 1 more.
So 5 + 6 = 11. We call these “doubles-plus-1 facts.” Children also learned doubles-plus-2
facts, such as 6 + 8. By adding 1 to the larger addend and subtracting 1 from the smaller
addend, children can use 7 + 7 = 14 to solve 6 + 8 = 14. Doubles-plus-2 facts can also
be solved by doubling the smaller number and adding 2 more. Review doubles-plus-1 and
doubles-plus-2 facts with your child.
Please return this Home Link to school tomorrow.
Write the sums. Tell someone at home how you can
use doubles facts to solve the problems.
1. 3 + 4 =
Copyright © Wright Group/McGraw-Hill
4.
2.
5.
8
+7
3. 7 + 5 =
=8+9
6.
5
+3
7.
4
+6
6
+5
Practice
Solve the riddles.
8. 2
and 4
=
9. 4
and 7
=
149
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