Standard 2.NBT.7: Add and subtract within 1000, using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method. Understand that in adding or subtracting three- digit numbers, one adds or subtracts hundreds and hundreds, tens and tens, ones and ones; and sometimes it is necessary to compose or decompose tens or hundreds.


Quarter 3
Quarter 4
Add and subtract within 1000, using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method. Understand that in adding or subtracting three- digit numbers, one adds or subtracts hundreds and hundreds, tens and tens, ones and ones; and sometimes it is necessary to compose or decompose tens or hundreds (without traditional algorithm).
Add and subtract within 1000, using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method. Understand that in adding or subtracting three- digit numbers, one adds or subtracts hundreds and hundreds, tens and tens, ones and ones; and sometimes it is necessary to compose or decompose tens or hundreds (with traditional algorithm).

Enduring Understanding

Understanding place value can lead to number sense and efficient strategies for computing with numbers.

Essential Questions

How does a digit's position affect its value?

Vocabulary (online dictionary, visual mathematics dictionary, HCPSS Vocabulary Cards)

place value, commutative property, associative property, identity property, compose, decompose

About the Math

Addition: When the parts of a set are known, addition is used to name the whole in terms of its parts.
Subtraction: In a part-part whole model when the whole is known and one of the parts, subtraction names the other part. This is called the "take away" model.
Subtraction can also find the difference between two whole values. To find the difference, you can count up from the smaller or down from the larger value, whichever is easier or makes sense. We sometimes overlook subtraction as the difference between two whole values and focus on the take away model. Both situations need to be part of instruction.

Rich Tasks for Multiple Means of Engagement, Expression, and Representation (UDL)

VDW-k-3.png
VDW-k-3.png

Teaching Student-Centered Mathematics, K-3


Rich Problems:
The ages of all of the members of your family total 120. In your class, are there more families whose ages total more than 120 than there are families whose ages total less than 120? (Lilburn and Ciurak, Investigations, Tasks and Rubrics to Teach and Assess Math,p 40)


Chapter 6, Strategies for Whole Number Computation, pages 157-172
Activity 6.1, Ten-Frame Adding and Subtraction, page 165
Activity 5.21, Numbers, Squares, Sticks, and Dots, page 146
Assessment note, pages 171-172
Expanded Lesson: Exploring Subtraction Strategies, pages 184-185
Activities for Flexible Thinking, pages 145-150

Learnzillion Video Resources (7 Lessons)

lz_2nbt7-7.png
Select image for lessons.

Print Resources

Braincompatible2-3.png
Brain Compatible Activities, Grades 2-3
Sum Roll, pages 24-26
Ball Toss, pages 27-30
Math Hockey, pages 31-34

developing_number_concepts2.png
Developing Number Concepts, Grade 2
Chapter 3: Number Combinations to 20, pages 99-172

puddle_questions2.png
Puddle Questions, Grade 2
Investigation 4: Equations Galore,
pages 36-43
numbersense1-2.jpg
Number Sense, Grades 1-2
Section 3: Exploring Mental Computation,
pages 55-100
Section 5: Exploring Number Relationships,
pages 131-156

mentalmathprimarygrades.png
Mental Math in the Primary Grades
Unit 4: Thinking Strategies for Larger Numbers,
pages 67-87

Family Math.png
Family Math
Double Digit, page 111
Dollar Digit, page 112
Reverse Double Digit, page 113
How Close Can You Get?, page 114
Find the Digits, pages 127-133
Nimble with Numbers, grades 2-3.png
Nimble with Numbers, Grades 2-3
Addition, pages 97-118
Subtraction, pages 119-144

hands-on_standards_1-2.png
Hands On Standards, Grade 1-2
Exploring Place Value, pages 40-41
Adding Without Regrouping, pages 44-45
Adding With Regrouping, pages 46-47
Subtracting Without Regrouping, pages 48-49
Subtracting With Regrouping, pages 50-51


roadstoreasoninggrade1.png
Roads to Reasoning, Grade 2
What's Wrong: The Tooth Fairy, page 24
What Would You Do?: Super Snacks, page 37
What Would You Do?: Double Dessert, page 40

Elementary Math with Pizzazz.png
Elementary Math with Pizzazz!, Grade 2
Operations: Regroup, pages 20, 22, 23, 24

Hands on Standards, grade 3-4.png
Hands On Standards, Grade 3-4
Adding and Subtracting, pages 20-21
Estimating the Sum or Difference, pages 22-23
read_it_draw_it.png
Read it, Draw it, Solve it, Grade 2
Regrouping, pages 103, 106-112

Supersource base ten blocks.png
The Super Source: Base Ten Blocks, Grade K-2
Race for a Flat, pages 58-61
Race to Clear the Mat, pages 62-65








Web Resources

games_centers.jpg
lessons.jpg
students_resources.jpg
video_segments.jpg
Games and Centers
Lessons
Student Resources
Video Segments
Adding Hundreds with Carrying
Adapted Mind online practice problems
Breaking Numbers Apart
lesson seed
Greg Tang Resources printable resources
Subtraction with Regrouping
Math Playground video (great for 4th quarter)
Subtracting Hundreds with Regrouping
Adapted Mind online practice problems
Addition with Regrouping
lesson plan
Matching Number Pairs to 200
DreamBox online activity
Two Digit Addition
Adapted Mind (great for 4th quarter)
Subtracting with Regrouping and Zeroes
Adapted Mind online practice problems
Saving Hundreds (missing addend)
lesson plan
Addition with Tens on the Number Line
DreamBox online activity
Learnzillion Video Resources
(7 Lessons)
Diffy (subtraction) online game

Addition on a Number Line Using Landmark Numbers
DreamBox online activity

Circle 99 -addition online game

Subtraction on a Number LIne Using Constant Difference
DreamBox online activity

Two Digit Subtraction with Regrouping
online game (standard algorithm)



Math Madness - missing addend
online game











Children's Literature

Mission Addition.png
Mission Addition
by Loreen Leedy
Subtraction Action.png
Subtraction Action
by Loreen Leedy
Centipede's 100 Shoes.png
Centipede's 100 Shoes
by Tony Ross
The Coin Counting Book.png

The Coin Counting Book
by Rozanne Williams
Math Curse.png
Math Curse
Jon Scieszka
The $1.00  word riddle book.png
The $1.00 Word Riddle Book
by Marilyn Burns
Pigs Will be Pigs.png

Pigs Will be Pigs
by Amy Axelrod
Two of Everything.png

Two of Everything
by Lily Toy Hong
Ten Sly Piranhas.png

Ten Sly Piranhas
by William Wise
The Grapes of Math.png
The Grapes of Math
Greg Tang







Questions/Comments:

Contact John SanGiovanni at jsangiovanni@hcpss.org.


Use and Sharing of HCPSS Website and ResourcesCreative_Commons.png
Howard County Public Schools Office of Elementary Mathematics Curricular Projects has licensed this product under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License.