3rd Grade Unit: Addition of Whole Numbers
Time for Unit: 12 days
Pre-Assessment: Choose from the following assessments to gauge your students’
background knowledge of addition of whole numbers- Houghton Mifflin Harcourt South
Carolina Math textbook p.64 or go to www.thinkcentral.com to access pre-assessments
related to your textbook.
Background Information:
 Generate strategies to add whole numbers up to 20
 Understand place value
 Use place value understanding and properties of operations to add and subtract
 Represent and solve problems involving addition and subtraction
 Knowledge of basic addition facts
In second grade:
 Students compared whole number quantities through 999 by using the terms is
less than, is greater than and is equal to and the symbols <, > and =. Students
also analyzed the magnitude of digits through 9,999 on the basis of their place
value.
 Students generated strategies to add and subtract pairs of two-digit whole
numbers with regrouping and generated addition and subtraction strategies to
find missing addends and subtrahends in number combination through 20.
 Students generated strategies to round numbers through 90 to the nearest 10
and analyzed the magnitude of digits through 9,999 on the basis of their place
values.
Common Core Standards:
3. NBT.1.Use place value understanding to round whole numbers to the nearest 10 or
100.
3. NBT.2 Fluently add and subtract within 1000 using strategies and algorithms based
on place value, properties of operations, and/or the relationship between addition and
subtraction.
3. OA.8 Solve two-step word problems using the four operations. Represent these
problems using equations with a letter standing for the unknown quantity. Assess the
reasonableness of answers using mental computation and estimation strategies
including rounding
3. OA.9 Identify arithmetic patterns (including patterns in the addition table or
multiplication table), and explain them using properties of operations. For example,
observe that 4 times a number is always even, and explain why 4 times a number can
be decomposed into two equal addends.
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3rd Grade Unit: Addition of Whole Numbers
South Carolina State Standards:
NOP-3-2.1 Compare whole number quantities through 999,999 by using the terms is
less than, is greater than, and is equal to and the symbols <, >, and=.
NOP-3-2.2 Represent in word form whole numbers through nine hundred ninety-nine
thousand.
The chart below is a teacher resource reference to addition and subtraction situations.
Table 1: Common Addition and Subtraction Situations
Result Unknown
Change Unknown
Start Unknown
Add to
Take
from
Put
together/
Take
apart
Compare
Two bunnies sat on the
grass. Three more bunnies
hopped there. How many
bunnies are on the grass
now?
2+3=?
Two bunnies were sitting
on the grass. Some more
bunnies hopped there. Then
there were five bunnies.
How many bunnies hopped
over to the first two?
2+?=5
Some bunnies were sitting
on the grass. Three more
bunnies hopped there. Then
there were five bunnies. How
many bunnies were on the
grass before?
?+3=5
Five apples were on the
table. I ate two apples. How
many apples are on the
table now?
5–2=?
Five apples were on the
table. I ate some apples.
Then there were three
apples. How many apples
did I eat?
5–?=3
Some apples were on the
table. I ate two apples. Then
there were three apples. How
many apples were on the
table before?
?–2=3
Total Unknown
Addend Unknown
Both Addends Unknown¹
Three red apples and two
green apples are on the
table. How many apples are
on the table?
3+2=?
Difference
Five apples are on the table.
Three are red and the rest
are green. How many apples
are green?
3 + ? = 5, 5 – 3 = ?
Grandma has five flowers.
How many can she put in her
red vase and how many in
her blue vase?
Difference Unknown
Bigger Unknown
Smaller Unknown
(“How many more?”
version): Lucy has two
apples. Julie has five
apples. How many
more apples does Julie
have than Lucy?
(Version
with “more”):
Julie has three more apples
than Lucy. Lucy has two
apples. How many apples
does Julie have?
(Version with “more”): Julie
has three more apples than
Lucy. Julie has five apples.
How many apples does Lucy
have?
(Version with “fewer”):
Lucy has 3 fewer apples
than Julie. Lucy has two
apples. How many apples
does Julie have?
(Version with “fewer”): Lucy
has 3 fewer apples than Julie.
Julie has five apples. How
many apples does Lucy
have?
(“How many fewer?”
version): Lucy has two
apples. Julie has five
apples. How many fewer
apples does Lucy have
than Julie?
5 = 0 + 5, 5 = 5 + 0
5 = 1 + 4, 5 = 4 + 1
5 = 2 + 3, 5 = 3 + 2
2 + 3 = ?, 3 + 2 = ?
5 – 3 = ?, ? + 3 = 5
2 + ? = 5, 5 – 2 = ?
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3rd Grade Unit: Addition of Whole Numbers
¹These take apart situations can be used to show all the decompositions of a given number. The
associated equations, which have the total on the left of the equal sign, help children understand that the
= sign does not always mean makes or results in but always does mean is the same number as.
²Either addend can be unknown, so there are three variations of these problem situations. Both Addends
Unknown is a productive extension of this basic situation, especially for small numbers less than or equal
to 10.
³For the Bigger Unknown or Smaller Unknown situations, one version directs the correct operation (the
version using more for the bigger unknown and using less for the smaller unknown). The other versions
are more difficult.
6 Adapted from Box 2-4 of Mathematics Learning in Early Childhood, National Research Council (2009,
pp. 32, 33).
Concepts: What students need to know
 Comparing numbers to 999 using <, >, =
 Add pairs of two-digit numbers with regrouping
 Find missing addends
 Round numbers to nearest 10
Skills—What students need to be able to do
 Round whole numbers to nearest 10s and 100s
 Fluently add within 1000 using strategies based on place value
 Fluently add within 1000 using strategies based on properties of operations
 Fluently add within 1000 using strategies based on the relationship of addition
 Represent problems using equations with a variable
 Identify arithmetic patterns
 Demonstrate a deep understanding of place value and number sense
 Explain and reason about the answers which are the result of rounding.
* NOTE: See attached ”Flipbook” .pdf for 3rdgrade math (From Arizona Dept.
of Ed.)- read pgs. 1-3 to gain insight into the standards of mathematical
practices for the 3rd grade content standards. Read the summary of skills and
sample questions to develop mathematical thinking and use this doc as a
guide during instruction.
Materials/ Manipulatives:
Number line
Place-value chart
Base-ten blocks
Balances
11-20 Unifix cubes per child
Grid paper
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3rd Grade Unit: Addition of Whole Numbers
Big Ideas:
 Place value is crucial when operating with numbers.
 Estimation helps us see whether or not our answers are reasonable
 Using rounding is an appropriate estimation strategy for solving problems and
estimating.
 Investigate, understand, and use place value to manipulate numbers.
 Build on understanding of place value to round whole numbers.
 Continue to develop understanding of addition and subtraction and use
strategies and properties to do so proficiently and fluently.
 Rounded numbers are approximate and not exact.
 Addition means the joining of two or more sets that may or may not be the same
size.
Lesson 1: Compare/Rounding
CCSSM:
3. NBT.1 Use place value understanding to round whole numbers to the nearest 10 or
100.
South Carolina State Standards:
NOP-3-2.1 Compare whole number quantities through 999,999 by using the terms is
less than, is greater than, and is equal to and the symbols >, <, =.
Standards for Mathematical Practices
5. Use appropriate tools strategically.
7. Look for and make use of structure.
8. Look for and express regularity in repeated reasoning.
Day 1
The teacher and students will complete the Every Day Counts Calendar activities.
The teacher will pose the following task for students to work first by themselves and
then discuss with a partner. Students will underline the important information (clues)
needed to solve the task and circle the question. Students will place all the information
on the chart in their Math Notebooks.
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3rd Grade Unit: Addition of Whole Numbers
Chart format:
Clues:
Question:
Strategy:
Explanation:
Solution (Write answer in a complete sentence.)
TASK
In June, Hickory Point sold 9, 567 bottles of soda. In July, they sold 11, 562 bottles of
soda. Estimate the number of bottles of soda sold at Hickory Point to see which month
sold the most. How do you know?
As students are working on the task, the teacher is walking around questioning students
and giving assistance needed without giving the answer of how to solve. After a period
of time, students will then discuss their solutions with a partner. Afterwards the teacher,
with the students, will model how to complete the chart.
Continue to use manipulatives such as hundreds charts and place-value charts. Have
students use a number line or a roller coaster example to block off the numbers in
different colors.
For example, this chart shows which numbers will round to the tens place.
Rounding can be expanded by having students identify all the numbers that will round to
30 or round to 200.
Give partners a number line from 0-100 marked in 10s.
Ask: Which number is greater: 45 or 73? Have students explain how to use the points
on the number line to find the greater number. Have them share their work and
explanations with other pairs. Ask: Where is 0 located on the number line? Which
number is farther away from 0 on the number line: 36 or 81? Which number is greater:
36 or 81? If you read the number on a number line from left to right, are you reading the
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3rd Grade Unit: Addition of Whole Numbers
number from least to greatest or greatest to least? Explain. Repeat the above process
using different numbers.
In student journals, have students work together to compare 2-digit numbers using a
number line. Write >, <, or =. 1. 34
64
2. 52
58
3. 81
76
Students will do a close reading* of the text in their textbook on page 26. As students
are reading, they should pay close attention to Examples on page 26 that explain three
ways to compare numbers. Students should take notes in their math notebooks of the
three ways using the graphic organizer below. Once students have completed the
examples in their notebooks, students will have a discussion about the content of the
examples with other students at their table. Afterwards, the class will come back
together to discuss what the examples mean.
* See Close Reading link for tips: https://www.criticalthinking.org/pages/critical-thinkingthe-art-of-close-reading-part-three/511
Or visit Saluda curriculum & instruction link: http://www.saludaschools.org/domain/5
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3rd Grade Unit: Addition of Whole Numbers
Example 1
Example 2
Compare Numbers
Example 3
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3rd Grade Unit: Addition of Whole Numbers
Through the teacher modeling, students will construct a three divided foldable to place
their vocabulary words and examples in.
Front
2 nd pg.
Ex.
>
Is GREATER than
_ __ _ _ _ _ _ _ _ _ _ _ _ _
cut each
section
<
Is less than
is equal to
=
Folded line
Formative Assessment:
Students will be assessed through the use of an exit ticket and/or quick checks using
dry-erase boards.
e.g.: Students will compare the following numbers using >, <, =.
45 ___ 54; 193 ___ 139; 204 ___ 204; 13,915 ___ 13,900
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3rd Grade Unit: Addition of Whole Numbers
Day 2:
The teacher and students will complete the Every Day Counts Calendar activities.
The teacher will pose the following task for students to work first by themselves and
then discuss with a partner. Students will underline the important information (clues)
needed to solve the task and circle the question. Students will place all the information
on the chart in their Math Notebooks.
TASK
In a teachers’ supply store, there are blue, red, and green pens for sale. Last month,
teachers bought 365 red pens and 382 green pens. Compare these numbers using the
sign < or >. Were more red pens or more green pens sold last month?
As students are working on the task, the teacher is walking around questioning students
and giving assistance needed without giving the answer of how to solve. After a period
of time, students will then discuss their solutions with a partner. Afterwards the teacher,
with the students, will model how to complete the chart.
Compare numbers using place-value positions from left to right. Introduce the placevalue chart as a means of comparing whole numbers. Students will draw a place-value
table in their notebooks to model its use when comparing whole numbers. Use the
following examples for students to practice with a partner: 4,321 ___ 4,312
TenThousands Hundreds Tens
thousands
4
3
2
4
3
1
2 tens is greater than 1 ten: 4,321 > 4,312
Ones
1
2
Ex: 63,104 ___ 63,104
5, 228 ___ 5,628
799 ___ 793
Activity:
Students will use decks of cards with cards 1(Ace)-9 and symbol cards made from
notecards.
1. Deal four cards from the top of the deck to each player.
2. Players use the four cards to make the largest three-digit number possible. Each
player discards one card.
3. Record your numbers and the number you decided to discard (put in the trash) on the
recording sheet.
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3rd Grade Unit: Addition of Whole Numbers
4. Players compare their numbers using the appropriate math talk sentence. The player
with the largest number for the round scores 1 point.
5. Repeat steps 1- 4 until six rounds have been played. The player with the largest total
number of points at the end of six rounds wins the game.
Formative Assessment:
Students will complete page 28 of their textbook #6-11 on their whiteboards.
Day 3
The teacher and students will complete the Every Day Counts Calendar activities.
The teacher will pose the following task for students to work first by themselves and
then discuss with a partner. Students will underline the important information (clues)
needed to solve the taskand circle the question. Students will place all the information
on the chart in their Math Notebooks.
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3rd Grade Unit: Addition of Whole Numbers
TASK
In a teachers’ supply store, there are blue, red, and green pens for sale. Last year,
teachers bought 7,606 blue pens, 8,094 red pens, and 7,543 green pens. What are
these numbers rounded to the nearest hundred?
As students are working on the task, the teacher is walking around questioning students
and giving assistance needed without giving the answer of how to solve. After a period
of time, students will then discuss their solutions with a partner. Afterwards the teacher,
with the students, will model how to complete the chart.
TEACHER INFORMATION:
“To round a number simply means to substitute a nice number that is close, so that
some computation can be done more easily.” Rounding is used to simplify computation
in a story, chart or conversation. For example, if you are talking about the amount of
time it takes you to do homework, most people will not say 57 minutes, they will say
about an hour. The first number is a precise amount of time. The second number refers
to an approximate amount of time for better communication. (Van de Walle p. 47)
Prior to implementing rules for rounding, students need to have opportunities to
investigate place value. A strong understanding of place value is essential for the
developed number sense and the subsequent work that involves rounding numbers.
Building on previous understandings of the place value of digits in multi-digit numbers,
place value is used to round whole numbers. Dependence on learning rules or
mnemonics can be eliminated with strategies such as the use of a number line to
determine which multiple of 10 or of 100 a number is closer. (5 or more rounds up, less
than 5 rounds down). As students’ understanding of place value increases, the
strategies for rounding are valuable for estimating, justifying, and predicting the
reasonableness of solutions in problem-solving.
Ask students when we would use rounding (e.g., going to the store to buy several
items). Rounding is a better “estimation” than front end estimation especially when
rounded numbers are added to estimate a sum. However, sums of rounded numbers
ARE NOT NECESSARILY THE EXACT SUMS OF THE ORIGINAL NUMBERS. They
are only a reasonable “guesstimation.”
Students learn when and why to round numbers. They identify possible answers and
halfway points. Then they narrow where the given number falls between the possible
answers and halfway points. They also understand that by convention if a number is
exactly at the halfway point of the two possible answers, the number is rounded up.
TASK
Part I
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3rd Grade Unit: Addition of Whole Numbers
The teacher will begin the lesson outside on the sidewalk. S/he will introduce the
decade numbers. The teacher may have the students count by 10s to 100. As the
students are counting the teacher will use sidewalk chalk to draw “islands” on the side
walk. Be sure to leave enough room in between each decade number to make the tick
marks for the numbers in between.
Next, the class will discuss what can go in between the decade numbers. Have the
groups of students, using sidewalk chalk, record the numbers that are in between the
decade numbers. Please note that the measurement between the numbers will probably
not be equal. As long as they do not skip any numbers it should be fine.
The teacher will now set the stage for rounding. You can start by asking a series of
questions:
• What is estimating?
• Does anyone know why we estimate?
Explain to the students that today they will learn a new estimation strategy. They are
going to round to the nearest 10. “Let’s look at the islands with the decade numbers,
what do you notice?” Students may respond with things like, the islands count by 10s,
or they are decade numbers.
When rounding, you are looking for nice numbers like the decade numbers. Ask a
student to stand on a number such as 43. The student will locate 43 on the number line
and stand there. The teacher will lead the students into a discussion about the nearest
decade number. They can even walk/hop to the closest island by counting the steps.
Continue this with other students allowing them to gain an understanding of the nearest
“nice number”. Please avoid teaching such things as, “5 or higher, and 4 or lower”. We
want students to conceptualize the rounding and not memorize rules. Allow students to
grapple with and discuss this in order to develop a deeper understanding.
Part II
Students will use the “Island Hop” Scavenger Hunt task sheet (below) to answer
questions about rounding. Students should use a number line (cut the attached 0-99
chart to create) or use the 0-99 chart to complete the task.
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3rd Grade Unit: Addition of Whole Numbers
Name_________________ Date__________________
THE ISLAND HOP SCAVENGER HUNT
1. I am a number that rounds to 40. What can I be? Could I be another number?
Justify your thinking.
2. I am a number that rounds to 90. What can I be? Could I be another number?
Justify your thinking.
3. I am a number that rounds to thirty. One of my digits is 2. What number am I?
Could I be another number? Justify your thinking.
4. I am a number that rounds to 60. What can I be? Could I be another number?
Justify your thinking.
5. Jalynn told Tameka that she has about 50 stickers. Tameka has 48 stickers.
Knowing that Jaylynn rounded her total, is it possible that Tameka has more stickers
than Jalynn? Justify your thinking using words, pictures and numbers.
6. Jay has about 70 baseball cards. Mark has 72 baseball cards. Is it possible for Jay
to have more baseball cards than Mark? Justify your thinking using words, pictures,
and numbers.
Formative Assessment:
Students will round the following examples on their whiteboards:
To nearest 10—86, 93, 362
To nearest 100—482, 377, 4597
Day 4
The teacher and students will complete the Every Day Counts Calendar activities.
The teacher will pose the following task for students to work first by themselves and
then discuss with a partner. Students will underline the important information (clues)
needed to solve the task and circle the question. Students will place all the information
on the chart in their Math Notebooks.
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3rd Grade Unit: Addition of Whole Numbers
TASK
The area of South Carolina is 31,189 square miles. What is the area of South Carolina
rounded to the nearest tens and nearest hundreds? Explain how you solved.
As students are working on the task, the teacher is walking around questioning students
and giving assistance needed without giving the answer of how to solve. After a period
of time, students will then discuss their solutions with a partner. Afterwards the teacher,
with the students, will model how to complete the chart.
Students will do a close reading* of the text in their textbook on page 34. As students
are reading, they should pay close attention to two ways to round numbers. Students
should take notes in their math notebooks of the two ways using the graphic organizer
below. Once students have completed the examples in their notebooks, students will
have a discussion about the content of the examples with other students at their table.
Afterwards, the class will come back together to discuss what the examples mean.
Title: Round to the Nearest Ten and Hundred
One way:
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Second Way
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3rd Grade Unit: Addition of Whole Numbers
Activity:
Students will use decks of playing cards to complete the activity following the directions
on the sheet.
Formative Assessment:
Students will complete the problems on page 35 # 2-8 of their text books on
whiteboards.
Lesson 2: Addition
CCSSM:
3. NBT.2 Fluently add and subtract within 1000 using strategies and algorithms based
on place value, properties of operations, and/or the relationship between addition and
subtraction.
3. OA.8 Solve two-step word problems using the four operations. Represent these
problems using equations with a letter standing for the unknown quantity. Assess the
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3rd Grade Unit: Addition of Whole Numbers
reasonableness of answers using mental computation and estimation strategies
including rounding.
3. OA.9 Identify arithmetic patterns (including patterns in the addition table or
multiplication table), and explain them using properties of operations. For example,
observe that 4 times a number is always even, and explain why 4 times a number can
be decomposed into two equal addends.
South Carolina State Standards:
NOP-3-2.2 Represent in word form whole numbers through nine hundred ninety- nine
thousand.
SMP:
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.
Day 5
The teacher and students will complete the Every Day Counts Calendar activities.
The teacher will pose the following rask for students to work first by themselves and
then discuss with a partner. Students will underline the important information (clues)
needed to solve the task and circle the question. Students will place all the information
on the chart in their Math Notebooks.
TASK
Maureen began a workout routine. Her workout was 15 minutes on the first day, 18
minutes on the second day, 21 minutes on the third day, 24 minutes on the fourth day,
and 27 minutes on the fifth day.
A. If the pattern continues, how many minutes will Maureen’s workout be on the
sixth day? Explain your answer.
B. Are the numbers of workout minutes odd or even? Explain your answer.
As students are working on thetask, the teacher is walking around questioning students
and giving assistance needed without giving the answer of how to solve. After a period
of time, students will then discuss their solutions with a partner. Afterwards the teacher,
with the students, will model how to complete the chart.
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3rd Grade Unit: Addition of Whole Numbers
Ideas/Strategies
Patterns:
Students need ample opportunities to observe and identify important numerical patterns
related to operations. They should build on their previous experiences with properties
related to addition and subtraction. Students investigate addition and multiplication
tables in search of patterns and explain why these patterns make sense mathematically.
For example:
 Any sum of two even numbers is even.
 Any sum of two odd numbers is even.
 Any sum of an even number and an odd number is odd.
 The multiples of 4, 6, 8, and 10 are all even because they can all be decomposed
into two equal groups.
 The doubles (2 addends the same) in an addition table fall on a diagonal while
the doubles (multiples of 2) in a multiplication table fall on horizontal and vertical
lines.
 The multiples of any number fall on a horizontal and a vertical line due to the
commutative property.
 All the multiples of 5 end in a 0 or 5 while all the multiples of 10 end with 0. Every
other multiple of 5 is a multiple of 10.
Students also investigate a hundreds chart in search of addition and subtraction
patterns. They record and organize all the different possible sums of a number and
explain why the pattern makes sense.
Teacher and students will use pages 18-21 of Buckle Down to the Common Core State
Standards as practice material. (addition patterns)
The teacher will need to spend some time talking about writing number names for
numbers. This concept is tested in 3rd grade but not on common core.
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3rd Grade Unit: Addition of Whole Numbers
Formative Assessment:
Students will be assessed through the use of an exit ticket and/or quick checks using
dry-erase boards.
Ex: patterns
Complete the number sentences.
3 + __ = 21
2 + __= 21
1 + __ = 21
What pattern do you notice in the number sentences?
Day 6
The teacher and students will complete the Every Day Counts Calendar activities.
The teacher will pose the following task for students to work first by themselves and
then discuss with a partner. Students will underline the important information (clues)
needed to solve the problem and circle the question. Students will place all the
information on the chart in their Math Notebooks.
TASK
During the week, Jon walked dogs a total of 118 times. Ben walked dogs 126 times.
How many times in all did Jon and Ben take dogs for a walk? Write your answer in
standard form and the number name.
As students are working on the task, the teacher is walking around questioning students
and giving assistance needed without giving the answer of how to solve. After a period
of time, students will then discuss their solutions with a partner. Afterwards the teacher,
with the students, will model how to complete the chart.
Missing Addends:
Students should be exposed to multiple problem-solving strategies (using any
combination of words, numbers, diagrams, physical objects or symbols) and be able to
choose which ones to use.
Examples:
The soccer club is going on a trip to the water park. The cost of attending the trip
is $63. Included in that price is $13 for lunch and the cost of 2 wristbands, one for
the morning and one for the afternoon. Write an equation representing the cost of
the field trip and determine the price of one wristband.
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3rd Grade Unit: Addition of Whole Numbers
w
w
13
63
The above diagram helps the student write the equation, w + w + 13 = 63. Using
the diagram, a student might think, “I know that the two wristbands cost $50
($63-$13) so one wristband costs $25.” To check for reasonableness, a student
might use front end estimation and say 60-10 = 50 and 50 ÷ 2 = 25.
Students will do a close reading* of the text in their textbook on page 46. As students
are reading, they should pay close attention to the vocabulary words: sum, addend, and
missing addend. Students will complete the vocabulary graphic organizer to include in
their math notebooks. Once students have completed the examples in their notebooks,
students will have a discussion about the content of the examples with other students at
their table. Afterwards, the class will come back together to discuss what the examples
mean.
Math Term
sum
Personal Definition
Mathematical Example
addend
missing addend
Formative Assessment:
Find the missing number for each.



___ + 55 = 73
85 + 15 = ___ + 15
(3 + ___) + 5 = 3 + ( 4 + 5)
Day 7
The teacher and students will complete the Every Day Counts Calendar activities.
The teacher will pose the following task for students to work first by themselves and
then discuss with a partner. Students will underline the important information (clues)
needed to solve the task and circle the question. Students will place all the information
on the chart in their Math Notebooks.
TASK
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3rd Grade Unit: Addition of Whole Numbers
A band played two concerts. The first concert had 375 people. The second concert
had 200 more people than the first concert. How many people attended the second
concert? Write the number sentence to solve and justify your solution.
As students are working on the task, the teacher is walking around questioning students
and giving assistance needed without giving the answer of how to solve. After a period
of time, students will then discuss their solutions with a partner. Afterwards the teacher,
with the students, will complete the chart.
The teacher will model using the base-ten blocks how to add and regroup two- threedigit numbers when needed. (Refer to page 52 of textbook) Students will draw pictures
to represent the sum in their math journals. After several modeling examples, the
students will practice adding three-digit numbers (use ex. on page 53 of textbook #1-6)
with a partner and drawing pictures of the sum in their math journals. The teacher will
walk around monitoring the process as students are working.
Formative Assessment:
The teacher will observe students as they model adding with the base-ten blocks and
drawing pictures of the sums in their math journals.
Day 8
The teacher and students will complete the Every Day Counts Calendar activities.
The teacher will pose the following task for students to work first by themselves and
then discuss with a partner. Students will underline the important information (clues)
needed to solve the task and circle the question. Students will place all the information
on the chart in their Math Notebooks.
TASK
There were 217 people at a play. Then 136 more people came. How many people
were at the play in all? Explain how you got your answer.
As students are working on the task, the teacher is walking around questioning students
and giving assistance needed without giving the answer of how to solve. After a period
of time, students will then discuss their solutions with a partner. Afterwards the teacher,
with the students, will model how to complete the chart.
The teacher will model using grid paper how to align numbers by place-value when
recording addition with regrouping. Next, the teacher will give each student grid paper
and help them write 454 + 788 vertically on the grid paper. As they work together, she
points to the ones column and asks if regrouping is necessary. Write the regrouped 1
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3rd Grade Unit: Addition of Whole Numbers
in the box above the tens column. Repeat for the tens column. Again asking if
regrouping is necessary. Have students continue the addition to find the sum.
As practice with finding the sum using an algorithm, assign page 53 #7-16 in the
students textbook. Students will also practice writing the word name for the sums of
#12-16.
Formative Assessment:
On an exit ticket, students will answer the following problem:
Susie sold 98 bags of popcorn on Monday and 323 bags on Tuesday. How many bags
of popcorn did she sell in the two days? Choose which example (s) has the correct
answer. If the answer is no, explain why for each of the responses.
1a. three hundred twenty-one
Yes O
No O
.
1 b. four hundred eleven
Yes O
No O
.
1c. four hundred twenty-one
Yes O
No O
1d. one thousand four hundred three
Yes O
No O
Day 9
The teacher and students will complete the Every Day Counts Calendar activities.
The teacher will pose the following task for students to work first by themselves and
then discuss with a partner. Students will underline the important information (clues)
needed to solve the task and circle the question. Students will place all the information
on the chart in their Math Notebooks.
TASK
Roger played a computer game twice. He scored four hundred twenty-eight points in his
first game. In the second game, he scored five hundred fifty-nine points. Estimate how
many points Roger scored. Write your answer in standard and word form.
As students are working on the task, the teacher is walking around questioning
students and giving assistance needed without giving the answer of how to solve. After
a period of time, students will then discuss their solutions with a partner. Afterwards the
teacher, with the students, will complete the problem solving chart.
Today students will continue to practice adding numbers, but will work on regular
notebook paper. Students typically have much problem with aligning numbers up
correctly when solving algorithms so practice is very valuable. Students will complete
the following worksheet.
The teacher will walk around monitoring the process as students are working. She will
make notes of students who may need extra help to pull during Power Period.
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3rd Grade Unit: Addition of Whole Numbers
Add.
1.
2
.
1
8
0
2
+
3.
6
8
1
2
4
+
2
4.
1
8
5
1
3
4
2
9
+
7.
2
0
6
+
8
3
1
5
5
3
6
7
9
3
2
1
8
6
6
2
4
9.
0
+
9
+
8
.
8
3
6.
6
+
1
+
3
5
.
8
4
+
5
2
10
.
12
.
1
4
9
9
+
1
+
6
Formative Assessment:
Students will answer the examples on their whiteboards.
Add:
1. 43 + 399
2. 456 + 275
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3rd Grade Unit: Addition of Whole Numbers
3. 589 + 53
4. 785 + 45
5. 208 + 496
6. 713 + 216
Day 10
.
The teacher and students will complete the Every Day Counts Calendar activities.
The teacher will pose the following task for students to work first by themselves and
then discuss with a partner. Students will underline the important information (clues)
needed to solve the task and circle the question. Students will place all the information
on the chart in their Math Notebooks.
TASK
The video game store is stocking up on the hottest new game. They already have one
hundred twenty-seven on the shelf, but they are selling quickly. They just received a
new shipment of three hundred eighty-four copies of the game. How many copies of
the game does the video game store have now? Show how you would solve the
problem.
As students are working on the task, the teacher is walking around questioning students
and giving assistance needed without giving the answer of how to solve. After a period
of time, students will then discuss their solutions with a partner. Afterwards the teacher,
with the students, will complete the problem solving chart.
Next, students will write a similar story about having a large shipment come into a store.
Students will share their problem with a table neighbor to solve. Once the partner has
solved, they will share their solution with the writer of the problem.
Estimate to Add:
When students solve word problems, they use various estimation skills which include
identifying when estimation is appropriate, determining the level of accuracy needed,
selecting the appropriate method of estimation, and verifying solutions or determining
the reasonableness of solutions.
Estimation strategies include, but are not limited to:
 using benchmark numbers that are easy to compute
 front-end estimation with adjusting (using the highest place value and estimating
from the front end making adjustments to the estimate by taking into account the
remaining amounts) rounding and adjusting (students round down or round up
and then adjust their estimate depending on how much the rounding changed the
original values)
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3rd Grade Unit: Addition of Whole Numbers
The teacher will model using rounding as a means of determining if the sum is
reasonable. The teacher will question students about how to round 325 + 87 in
determining if their solution is reasonable. The process of rounding is being reviewed
from the first part of this unit.
+
325
300
98
+ 100
400
4 problems # 2-6 from page 49 of their textbook in their math
Students will complete
notebooks. The teacher will walk around monitoring the process as students are
working. She will make notes of students who may need extra help to pull during Power
Period.
Formative Assessment:
On an exit ticket, students will answer the following problem.
Shorelines of Texas Lakes
Lake
Lake Fork
Lake Conroe
Lake Buchanan
Distance in miles
315
157
124
Some lakes in Texas have shorelines along which people hike and fish. EXPLAIN how
you would estimate the sum of Lake Fork’s and Lake Conroe’s shoreline.
Day 11
The teacher and students will complete the Every Day Counts Calendar activities.
The teacher will pose the following task for students to work first by themselves and
then discuss with a partner. Students will underline the important information (clues)
needed to solve the task and circle the question. Students will place all the information
on the chart in their Math Notebooks.
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3rd Grade Unit: Addition of Whole Numbers
TASK
The third grade sold two hundred sixty-four tickets to the Fall Festival. The second
grade sold one hundred twenty-nine tickets. How many tickets did they sell together?
Write your answer in standard and word form.
As students are working on the task, the teacher is walking around questioning
students and giving assistance needed without giving the answer of how to solve. After
a period of time, students will then discuss their solutions with a partner. Afterwards the
teacher, with the students, will complete the problem solving chart.
Teacher will show the video of the Commutative Property of Addition on
www.brainpop.com. Use the following user name: bufsd and password: bufsd
Stop the video as it begins to talk about multiplication. Go to the FYI: Read more
activity on the web-site. Students will take note about the Commutative Property of
Addition in their Math Notebooks. Students will read and discuss the real-life problems
with their partner and come up with 3 other real-life examples that show the
Commutative Property of Addition. Students will write the examples in their math
notebooks. The group will come back together and discuss their real life examples.
Next, the teacher will show the video of the Associative Property of Addition on
www.brainpop.com. Students will take note about the Commutative Property of
Addition in their Math Notebooks. After watching the video, students will discuss the
Associative Property of Addition with a partner and develop 3 examples to write in their
math notebooks. Afterwards the class will come back together to share their examples.
Formative Assessment:
Students will answer the following examples on their whiteboard for a quick
assessment.
1. The commutative property of addition states that the order of the numbers in an
equation:
a. Should go from smallest to largest
b. Should go from largest to smallest
c. Is important
d. Doesn’t change the sum
2. According to the commutative property of addition, 2 + 5 equals:
a. 6 + 1
b. 3 + 4
c. 5 + 2
d. 4 + 3
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3rd Grade Unit: Addition of Whole Numbers
3. According to the commutative property of addition, 3 + 4 + 6 equals:
a. (3 + 4) + (3 + 6)
b. ( 3 + 4) x ( 3 + 6)
c. 4 + 5 + 7
d. 6 + 3 + 4
4. According to the associative property of addition, (k + 4) + 6 =
a. k + 4 + 6
b. (k + 4) + (k + 6)
c. k + (4 + 6)
d. 10k
5. Which show the associative property of addition?
a. x + y + z= (x + y) + (x + z)
b. x + y = y + x
c. x + (y + z)= (x + y) + z
d. x + (y + z) + (xy) + (xz)
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3rd Grade Unit: Addition of Whole Numbers
Summative Assessment:
1. Which two of the items above would provide a total of about 600 calories?
Answer:____________________
____________________
POINTS EARNED FROM SCHOOL EVENTS
2.
a.
b.
c.
d.
Class
Mathathon
Readathon
Mr. Lopez
425
411
Ms. Chen
328
456
Mrs. Green
447
342
What was the total number of points earned from the Mathathon?
753
775
1200
1209
3. The weight of an object is 1,700 pounds, rounded to the nearest hundred. Of the
following, which could be the actual weight of the object?
A.
B.
C.
D.
E.
1,640
1,645
1,649
1,749
1,751
4. The length of a dinosaur was reported to have been 80 feet (rounded to the nearest
10 feet). What length other than 80 feet could have been the actual length of this
dinosaur? Answer:____________________ feet
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3rd Grade Unit: Addition of Whole Numbers
5. The census showed that three hundred fifty-six thousand, ninety-seven people lived
in Middletown. Written as a number, that is
A.
B.
C.
D.
350,697
356,097
356,907
356,970
6. The 421 students at Eagle School are going on a trip to the zoo. There are two types
of buses; one bus holds 72 students and the other bus hold 58 students. There are also
20 teachers going on the bus to supervise the students. What type of bus and how
many buses are needed to make sure that all 421 students are able to go swimming?
Explain how you would solve the problem.
7. There are 30 legs in my backyard, but I’m counting dogs and kids. How many dogs
and kids are in my backyard? Show the step(s) used to solve the problem.
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