Unit Overview
Content Area: Math
Unit Title: Addition of 2-Digit Numbers with/without Regrouping
Target Course/Grade Level:
2
Unit: 5
Timeline: 4 weeks/ongoing
Unit Summary: Students will learn to regroup so they can accurately add two digit numerals.
Primary interdisciplinary connections: Language Arts
NJ Standard 9.1: 21st – Century Life & Career Skills
Standard 9.1: All students will demonstrate the creative, critical thinking, collaboration, and problemsolving skills needed to function successfully as both global citizens and workers in diverse ethnic and
organizational cultures.
Strand: A. Critical Thinking and Problem Solving
C. Collaboration, Teamwork and Leadership
Content Statement:
9.1.4.A.5: The ability to recognize a problem and apply critical thinking and problem-solving
skills to solve the problem is a lifelong skill that develops over time.
9.1.4.C.1: Practice collaborative skills in groups, and explain how these skills assist in
completing tasks in different settings such as home, play or school.
21st century themes and skills: Critical Thinking and Problem Solving, Collaboration, Teamwork and
Leadership
Mathematical Practices:
2.MP.1. Make sense of problems and persevere in solving them.
2.MP.2. Reason abstractly and quantitatively.
2.MP.3. Construct viable arguments and critique the reasoning of others.
2.MP.4. Model with mathematics.
2.MP.5. Use appropriate tools strategically.
2.MP.6. Attend to precision.
2.MP.7. Look for and make use of structure.
2.MP.8. Look for and express regularity in repeated reasoning.
Learning Targets
Domain: Numbers and Operations in Base Ten 2.NBT
Measurement and Data 2.MD
Operations and Algebraic Thinking 2.OA
Cluster:
Use place value understanding and properties of operations to add and subtract.
Work with time and money.
Represent and interpret data.
Standard #
Standards
2.NBT.5
Fluently add and subtract within 100 using strategies based on place value, properties of
operations, and/or the relationship between addition and subtraction.
2.NBT.6
Add up to four two-digit numbers using strategies based on place value and properties of
operations.
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.
2.NBT.8
Mentally add 10 or 100 to a given number 100–900, and mentally subtract 10 or 100 from
a given number 100–900.
2.NBT.9
Explain why addition and subtraction strategies work, using place value and the properties
of operations.
2.MD.8
Solve word problems involving dollar bills, quarters, dimes, nickels, and pennies, using $
and ¢ symbols appropriately. Example: If you have 2 dimes and 3 pennies, how many
cents do you have?
2.MD.10
Draw a picture graph and a bar graph (with single-unit scale) to represent a data set with
up to four categories. Solve simple put-together, take-apart, and compare problems using
information presented in a bar graph.
2.OA.1
Use addition and subtraction within 100 to solve one- and two-step word problems
involving situations of adding to, taking from, putting together, taking apart, and
comparing, with unknowns in all positions, e.g., by using drawings and equations with a
symbol for the unknown number to represent the problem.
CPI#
Cumulative Progress Indicator (CPI)
9.1.4.A.5
Apply critical thinking and problem-solving skills in classroom and family settings.
9.1.4.C.1
Practice collaborative skills in groups, and explain how these skills assist in completing
tasks in different settings (at home, in school, and during play).
Unit Essential Questions
 How can I use what I know about number
relationships to add and subtract?

Why is recognizing what strategy to use
for a specific purpose, helpful?
Unit Enduring Understandings
 Different strategies (mental, paper, drawing)
can be used to add numbers fluently.

The same strategies used for two two-digit
numbers can be applied when adding three
or more than two-digit numbers.

Different strategies (mental, paper, drawing,
concrete models) can be applied to add
within 100.

Place value affects the other place values
when adding (regrouping, trading,
composing/decomposing)

When adding two-digit numbers, knowing
the value of that digit, in a given position,
determines the next step one must take to
solve an equation.

Multiples of 10 and 100 can be used as
landmark numbers in computation.

Words or drawings can be used to explain
addition strategies.

Money knowledge can be used to solve word
problems.

Picture & Bar graphs charts and tables can
be used to solve comparative and addition
problems.
Unit Learning Targets
Students will ...
 Use manipulatives to show regrouping of tens and ones.
 Explain how regrouping is done and represent with manipulatives.
 Compute addition problems of 2 digit numbers (w/&w/o regrouping)
 Add a 1 digit to a 2 digit and record in vertical format.
 Calculate sums of money to $.99.
 Add 3 two-digit addends.
 Solve problems involving addition using data from a table.
 Recognize and use different strategies/tools (calculator, manipulatives, drawings, number line,
mental math) to add 2 two-digit numbers.
 Solve a problem by using estimation to determine reasonableness of the sum.
 Use clue words to prompt solving word problems for double digit addition.
Evidence of Learning
Summative Assessment
 Illustrate/explain adding two-digit numbers with/without regrouping.
 Accurately compute two & three, two-digit numbers with/without regrouping for addition.
 Accurately compute money sums up to $.99 using two, two-digit numbers.
 Give a table with various two-digit numbers and solve addition with/without regrouping.
 Choose from a list of strategies/tools one could use to solve a given two-digit math addition
equation to determine which is the best way to attain the correct answer.
 Give an equation using 2 two-digit numbers. Solve the problem giving and estimate and exact
sum.
 Identify clue word (highlight, circle or underline) that indicates addition for a word problem and
write the equation with correct answer.
Equipment needed: place value cubes; multiple decks of cards; dice.
Teacher Instructional Resources:
Everyday Math
Math Their Way
Scott Foresman Mathematics Program: Chapter 5
Formative Assessments
Observe students as they ….
 work with manipulatives
 complete work sheets/workbooks
 play games, complete activities
Integration of Technology:
SMARTBoard to play online games and utilize on line resources.
ELMO to use for demonstration purposes.
Utilize resources from Scott Foresman by using Login in:
https://www.pearsonsuccessnet.com/snpapp/login/login.jsp
Technology Resources:
Click the links below to access additional resources used to design this unit:
http://www.dositey.com/addsub/mystery2A.htm A list of double digit horizontal problems appear with an
array of answers. When answers are figured out student presses on problem and then the answer and part
of a picture appears. Get all answers right and picture comes alive for a moment.
http://resources.oswego.org/games/ghostblasters2/gb2nores.html Student clicks on 2 numbers that add up
to target number to get rid of ghosts.
http://www.aplusmath.com/games/matho/AddMatho.html A vertical two digit addition problem appears
with an array of answers on a grid. Student presses on answer when it is determined. Game is played with
an automatic timer. Goal is to beat last score.
Opportunities for Differentiation:
Decelerate: Continue using place value blocks and/or beans for longer time so the concept of regrouping
is clearly understood. Use the Scott Foresman online tools to give another visual aide for learning the
concept.
Accelerate: Give students four, five and/or six digit numbers to add.
Teacher Notes: It is very important to make sure your students understand the concrete concept behind
regrouping. This is done by using the manipulatives and having the students verbalize what they are doing
and why in relationship to the problem.