Standard 2: Add and subtract two- and three-digit whole numbers.

General Information
Number: MA.2.NSO.2
Title: Add and subtract two- and three-digit whole numbers.
Type: Standard
Subject: Mathematics (B.E.S.T.)
Grade: 2
Strand: Number Sense and Operations

Related Benchmarks

This cluster includes the following benchmarks.

Related Access Points

This cluster includes the following access points.

Access Points

MA.2.NSO.2.AP.1
Recall addition facts with sums to 10 and related subtraction facts.
MA.2.NSO.2.AP.2
Identify the number that is ten more or ten less than a given two-digit number.
MA.2.NSO.2.AP.3
Apply a strategy for adding and subtracting a two-digit number (from 11 to 19) and a single digit whole number.
MA.2.NSO.2.AP.4
Explore the addition of a two-digit and a single-digit whole number with sums up to 100. Explore the subtraction of a one-digit from a two-digit whole number.

Related Resources

Vetted resources educators can use to teach the concepts and skills in this topic.

Formative Assessments

Explaining the Standard Algorithm for Subtraction:

Students are asked to explain each step of a subtraction problem completed by using the standard algorithm.

Type: Formative Assessment

Explaining the Standard Algorithm for Addition:

Students are asked to explain each step of an addition problem completed by using the standard algorithm.

Type: Formative Assessment

Subtract 10 Mentally:

Students are given three-digit numbers and asked to mentally subtract 10 from each number.

Type: Formative Assessment

Mentally Subtract 100:

Students are given three-digit numbers and asked to mentally add 100 to each number.

Type: Formative Assessment

Mentally Add 10 More:

Students are given three-digit numbers and asked to mentally add 10 to each number.

Type: Formative Assessment

Add 100 Mentally:

Students are given three-digit numbers and asked to mentally add 100 to each number.

Type: Formative Assessment

Differences on a Number Line:

Students use a number line to find to the difference between 17 and 42.

Type: Formative Assessment

Fluently Subtract Within 100:

Students are asked to solve three subtraction within 100 problems and are observed for the use of place value strategies.

Type: Formative Assessment

Adding Within 100 Using Place Value:

Students are asked to solve two addition problems and are observed for the use of place value strategies.

Type: Formative Assessment

Adding Within 1,000:

Students are asked to solve an addition problem within 1,000.

Type: Formative Assessment

Subtracting within 1,000:

Students are asked to solve a subtraction problem within 1,000.

Type: Formative Assessment

Mr. Ford’s Money:

Students are asked to solve a subtraction problem involving money.

Type: Formative Assessment

Sums on a Number Line:

Students use a number line to add 23 and 19 and to find a segment whose length is the sum of 23 and 19.

Type: Formative Assessment

Using Place Value:

Students are asked to solve a two-digit addition problem using a place value strategy and then are asked to explain why this strategy works.

Type: Formative Assessment

Counting Up To Subtract:

Student are asked to consider why a counting strategy works to solve subtraction problems.

Type: Formative Assessment

Using Properties and Place Value to Add and Subtract:

Students are asked to complete addition and subtraction problems that can be done efficiently by using properties of operations.

Type: Formative Assessment

Crossing a Decade:

The student is asked to solve an addition and a subtraction problem in which a decade (i.e., a multiple of ten) must be crossed.

Type: Formative Assessment

Place Value Strategies for Addition and Subtraction:

Students explain another student's written strategy for adding and written strategy for subtracting three-digit numbers.

Type: Formative Assessment

Fluency for Subtraction Within 20:

Students are asked to solve six subtraction within 20 problems and to explain their strategies for solving each problem.

Type: Formative Assessment

Fluency for Addition Within 20:

Students are asked to solve six addition within 20 problems and to explain their strategies for solving each problem.

Type: Formative Assessment

Fluency with Basic Addition Facts:

Students are assessed on their fluency with addition facts within 20.

Type: Formative Assessment

Addition Facts from Memory:

Students are assessed on a set of basic addition facts within 20.

Type: Formative Assessment

Subtracting Multiples of Ten:

Students find the difference between two multiples of 10.

Type: Formative Assessment

Subtracting Forty:

Students subtract 40 from 80 using linking cubes as a model.

Type: Formative Assessment

Jumping Rope:

Students add a multiple of 10 to a two-digit number.

Type: Formative Assessment

Adding Tens to Numbers:

Students add a multiple of 10 to a two-digit number and are asked to relate the strategy used to a written method.

Type: Formative Assessment

Lesson Plans

Hop Up, Hop Down- Three-Digit Numbers:

In this lesson, the students will be adding and subtracting 10 or 100 to/from a given three-digit number. The students will recognize patterns that occur and use these patterns to mentally identify the number that is 10 or 100 more or less than a given number.

Type: Lesson Plan

Trip to Statue of Liberty:

Students will discuss facts about the Statue of Liberty and take a virtual tour. Students will use tables of ferry ticket and food prices to solve one and two-step word problems involving money. 

Type: Lesson Plan

COUNTING ON RESPONSIBLE CITIZENSHIP (Lesson 3 of 3):

In this math/civics lesson integrated lesson students will create a pictograph based on data collected from 3 short stories realted to ressponisble and irrsponsible citizenship. 

 

Type: Lesson Plan

FLUENCY AND FLAG WAVERS An Integrated Math and Civics Mini Unit PART 3 :

Students will play a fluency game adding within 20 using playing cards.  There will be Responsible/Irresponsible Citizen cards embedded in the deck of cards that will result in an advantage or disadvantage in the game.  This integrated lesson is part 3 of 3 in a mini unit. 

 

Type: Lesson Plan

FLUENCY AND FLAG WAVERS An Integrated Math and Civics Mini Unit Part 2:

Students will circulate the room to find a partner who has an addend card that equals 20 with their addend card.  The activity will include matching behaviors that are examples of responsible and irresponsible citizenship. This integrated lesson is part 2 of 3 in a mini unit. 

Type: Lesson Plan

FLUENCY AND FLAG WAVERS An Integrated Math and Civics Mini Unit PART 1 :

Students will work in small groups to play a sum game taking turns finding 2 addends that equal a specific number within 20.  Throughout the game, the teacher will be giving students cards representing responsible behaviors that will give an advantage or irresponsible behaviors that will cause a disadvantage.  This integrated lesson is part 1 of 3 in a mini unit. 

Type: Lesson Plan

How Much Do We Need to Order?:

Students are provided the task of determining the total number of students in Kindergarten, first, and second grades in their school. Students will develop a plan to collect the information. Students will create a table to represent the data and find the total number of students.

Type: Lesson Plan

Let's Play!:

In this Model Eliciting Activity, MEA, students must decide the best way to spend the money earned in a fundraiser to buy new playground equipment.

Model Eliciting Activities, MEAs, are open-ended, interdisciplinary problem-solving activities that are meant to reveal students’ thinking about the concepts embedded in realistic situations. MEAs resemble engineering problems and encourage students to create solutions in the form of mathematical and scientific models. Students work in teams to apply their knowledge of science and mathematics to solve an open-ended problem, while considering constraints and tradeoffs. Students integrate their ELA skills into MEAs as they are asked to clearly document their thought process. MEAs follow a problem-based, student centered approach to learning, where students are encouraged to grapple with the problem while the teacher acts as a facilitator. To learn more about MEA’s visit: https://www.cpalms.org/cpalms/mea.aspx

Type: Lesson Plan

Fundraising on a Budget:

This Model-Eliciting Activity (MEA) is designed for a second grade level. Students will be working in small groups to figure out what companies to hire for the art gallery to have a successful charity event. The students will be evaluating criteria such as bands for the event, caterers, and artists. Students will need to add money to stay within a budget. They will write their procedure for making their selections.

Model Eliciting Activities, MEAs, are open-ended, interdisciplinary problem-solving activities that are meant to reveal students’ thinking about the concepts embedded in realistic situations. Click here to learn more about MEAs and how they can transform your classroom.

Type: Lesson Plan

Give A Cheer MEA!:

In this Model Eliciting Activity, MEA, The Give A Cheer Yearbook Committee needs the students' assistance to determine the best company to purchase the school yearbooks. Students will need to consider the cost, tax, and delivery time in their decision. In a “twist,” students are given additional information about shipping cost and are asked to determine if their procedure for ranking should change.

Model Eliciting Activities, MEAs, are open-ended, interdisciplinary problem-solving activities that are meant to reveal students’ thinking about the concepts embedded in realistic situations. MEAs resemble engineering problems and encourage students to create solutions in the form of mathematical and scientific models. Students work in teams to apply their knowledge of science and mathematics to solve an open-ended problem, while considering constraints and tradeoffs. Students integrate their ELA skills into MEAs as they are asked to clearly document their thought process. MEAs follow a problem-based, student centered approach to learning, where students are encouraged to grapple with the problem while the teacher acts as a facilitator. To learn more about MEA’s visit: https://www.cpalms.org/cpalms/mea.aspx


Type: Lesson Plan

Pirate Party! - Let's Make a Ten:

This lesson teaches students how to apply the "make-a-ten" strategy to addition problems involving two-digit addends.

Type: Lesson Plan

Roll and Add Two Digit Numbers:

In this lesson students will use two dice to roll and add two-digit numbers. Students will also use their numbers to create and solve one-step addition word problems.

Type: Lesson Plan

Disappearing Tens:

Students learn to subtract multiples of ten from multiples of ten by playing a game.

Type: Lesson Plan

Water Parks Galore!:

In this Model Eliciting Activity, MEA, students will devise a procedure, and justify it, in order to determine the best features of a water park. Students will use problem-solving skills and data sets presented in a bar graph and table. In a “twist,” students will be given new information and asked to determine whether their procedure still works. Students will create a bar graph representing the new data.

Model Eliciting Activities, MEAs, are open-ended, interdisciplinary problem-solving activities that are meant to reveal students’ thinking about the concepts embedded in realistic situations. MEAs resemble engineering problems and encourage students to create solutions in the form of mathematical and scientific models. Students work in teams to apply their knowledge of science and mathematics to solve an open-ended problem, while considering constraints and tradeoffs. Students integrate their ELA skills into MEAs as they are asked to clearly document their thought process. MEAs follow a problem-based, student centered approach to learning, where students are encouraged to grapple with the problem while the teacher acts as a facilitator. To learn more about MEA’s visit: https://www.cpalms.org/cpalms/mea.aspx

Type: Lesson Plan

Class Pets:

In this Model Eliciting Activity, MEA, students will devise a plan for ranking, and justify it, in order to choose the best class pet. Students will use problem-solving skills, interpret data presented in tables, add two-digit numbers, compare two and three-digit numbers, and create bar graphs.

Model Eliciting Activities, MEAs, are open-ended, interdisciplinary problem-solving activities that are meant to reveal students’ thinking about the concepts embedded in realistic situations. MEAs resemble engineering problems and encourage students to create solutions in the form of mathematical and scientific models. Students work in teams to apply their knowledge of science and mathematics to solve an open-ended problem, while considering constraints and tradeoffs. Students integrate their ELA skills into MEAs as they are asked to clearly document their thought process. MEAs follow a problem-based, student centered approach to learning, where students are encouraged to grapple with the problem while the teacher acts as a facilitator. To learn more about MEA’s visit: https://www.cpalms.org/cpalms/mea.aspx

Type: Lesson Plan

Cookie Contest:

In this Model Eliciting Activity, MEA, students are asked to decide which factors are important in choosing the best cookie in a cookie contest. Students will take on the role of cookie critics to provide feedback to a teacher whose grade level is deciding which cookie to use for a fundraiser. They will rank order their choices from the best to worst cookie. Students will provide a detailed written explanation for how they decided to rank factors and their solution. They will show their work while adding up to 4 two-digit numbers to calculate the total number of votes.

Model Eliciting Activities, MEAs, are open-ended, interdisciplinary problem-solving activities that are meant to reveal students’ thinking about the concepts embedded in realistic situations. MEAs resemble engineering problems and encourage students to create solutions in the form of mathematical and scientific models. Students work in teams to apply their knowledge of science and mathematics to solve an open-ended problem, while considering constraints and tradeoffs. Students integrate their ELA skills into MEAs as they are asked to clearly document their thought process. MEAs follow a problem-based, student centered approach to learning, where students are encouraged to grapple with the problem while the teacher acts as a facilitator. To learn more about MEA’s visit: https://www.cpalms.org/cpalms/mea.aspx

Type: Lesson Plan

Cellular Satisfaction:

In this Model Eliciting Activity, MEA, a client is searching for the best cell phone carrier. Students will determine a procedure for ranking the companies based on votes for the favorite company and fees. The data is given in a scaled bar graph and a table. In a “twist,” the client provides more data, presented in a scaled pictograph, for the students to consider.

Model Eliciting Activities, MEAs, are open-ended, interdisciplinary problem-solving activities that are meant to reveal students’ thinking about the concepts embedded in realistic situations. MEAs resemble engineering problems and encourage students to create solutions in the form of mathematical and scientific models. Students work in teams to apply their knowledge of science and mathematics to solve an open-ended problem, while considering constraints and tradeoffs. Students integrate their ELA skills into MEAs as they are asked to clearly document their thought process. MEAs follow a problem-based, student centered approach to learning, where students are encouraged to grapple with the problem while the teacher acts as a facilitator. To learn more about MEA’s visit: https://www.cpalms.org/cpalms/mea.aspx

Type: Lesson Plan

Best Classroom Pet:

In this Model Eliciting Activity, MEA, the students will work in teams to use data to determine which classroom pet teachers should get for their classrooms based on several characteristics.

Model Eliciting Activities, MEAs, are open-ended, interdisciplinary problem-solving activities that are meant to reveal students’ thinking about the concepts embedded in realistic situations. MEAs resemble engineering problems and encourage students to create solutions in the form of mathematical and scientific models. Students work in teams to apply their knowledge of science and mathematics to solve an open-ended problem, while considering constraints and tradeoffs. Students integrate their ELA skills into MEAs as they are asked to clearly document their thought process. MEAs follow a problem-based, student centered approach to learning, where students are encouraged to grapple with the problem while the teacher acts as a facilitator. To learn more about MEA’s visit: https://www.cpalms.org/cpalms/mea.aspx

Type: Lesson Plan

Birthday Parties 'R' Us:

Students will determine which pizza place should be used to cater parties at the Birthday Parties 'R' Us facility given a set of data. They will create a procedure for determining the best pizza place, write an explanation about their procedure, and present their recommendations to the class.

Model Eliciting Activities, MEAs, are open-ended, interdisciplinary problem-solving activities that are meant to reveal students’ thinking about the concepts embedded in realistic situations. Click here to learn more about MEAs and how they can transform your classroom.

Type: Lesson Plan

Mental Math Mania:

This is a lesson that will ensure students walk away with the vital skill of mentally finding 10 or 100 more or 10 or 100 less than a given three-digit number. There is a partner game included with a little competition involved.

Type: Lesson Plan

Rip and Regroup to Add:

Students will learn how to transpose a horizontal addition equation with two-digit addends using a specialized vertical place value work mat. Students will "rip and regroup" to help understand how to regroup ten ones as one ten and move toward using a standard algorithm for addition.

Type: Lesson Plan

Exploring Three-Digit Subtraction Strategies:

Students will explore various strategies to learn how to subtract three-digit whole numbers when regrouping across one place value is required.

Type: Lesson Plan

Adding and Subtracting on a Hundred Chart:

This lesson is not an introduction to adding and subtracting on the hundreds chart, but rather a practice of strategies to help develop procedural reliability. Students will use the hundred chart to add two two-digit numbers and subtract two-digit numbers from two-digit numbers to reveal hidden designs on the charts. Students will be encouraged to use place value to decompose the two-digit number that is being added or subtracted into tens and ones and then use the structure of the hundred chart to efficiently add the tens by moving up or down full rows before counting on or counting back the number of remaining ones.

Type: Lesson Plan

Alternative Addition Strategies:

This lesson explores various addition strategies of two-digit numbers. The lesson focus is to encourage students to find and develop a reliable method they can use to add within 100. The lesson includes making an Addition Strategies Mini Booklet, which students can keep and use as a reference tool.

Type: Lesson Plan

How Many Inches, Feet, and Yards?:

Students will measure the length of given objects using various measuring tools. The students will record their measurements using different units including inches, feet, and yards to the nearest whole unit. Students will also estimate and measure the lengths of objects, then compare their estimations to their measurements to find the difference.

 

Type: Lesson Plan

Is it "Most Magically Magical"?:

This lesson is intended to be a cooperative inquiry-based activity used close to the end of second grade. The students will be actively engaged in adding and subtracting numbers within 100 while having fun completing Magic Squares.

Type: Lesson Plan

Place Value - 3 Digit Numbers:

Students will decompose numbers by place value and represent them using concrete and pictorial models.

Type: Lesson Plan

Success with Story Problems - Addition/Subtraction:

In this lesson, students will solve one and two-step real-world problems using a variety of problem-solving strategies.

Type: Lesson Plan

Sweet Addition and Subtraction:

This lesson is a continuation of the "Sweet Values" and "Sweet Number Places" lessons also found on CPALMS. It is a different way of teaching addition and subtraction, by continuing a story that started with place value. In this lesson, students will learn to use the place value knowledge gained to solve word problems.

Type: Lesson Plan

Sweet Mental Math:

In this lesson students will learn to use the place value knowledge gained to identify the number that is 10 more, 10 less, 100 more, or 100 less than a given number. This is the continuation of a story found in previous lessons "Sweet Addition and Subtraction"and "Sweet Place Values."

Type: Lesson Plan

Sweet Number Places:

This lesson is a continuation of the Sweet Values CPALMS lesson Resource 46493 and is a different way of teaching place value, with a story that you can continue to use to also teach addition and subtraction to your second graders. In this lesson students will learn to numerically represent numbers in different ways and understand that the three digits in a three-digit number represent amounts of hundreds, tens, and ones.

Type: Lesson Plan

Sweet Values:

This lesson is a different way of teaching place value, with a story that you can continue to use to also teach addition and subtraction to your second graders. In this lesson students will learn to represent numbers in different ways and understand that the three digits in a three-digit number represent amounts of hundreds, tens, and ones.

Type: Lesson Plan

Tic Tac Toe by Tens and Hundreds:

This is an engaging hands-on activity which challenges students as they learn to find 10 or 100 more or less than a given number three-digit number.

Type: Lesson Plan

Original Student Tutorials

Place Value Party - Part 5: 100 Less:

Learn how to create numbers that are 100 less as you wrap up the place value party in this interactive tutorial.

This is part 1 in five-part series. Click below to view the other tutorials in the series.

 

Type: Original Student Tutorial

Place Value Party - Part 4:

Find 100 less and 100 more than a given 3-digit number by helping Kaylin and Quinten keep track of the place value party game points in this interactive tutorial.

 

This is part 1 in five-part series. Click below to view the other tutorials in the series.

Type: Original Student Tutorial

Place Value Party - Part 2:

Find 10 more and 10 less than 3-digit numbers with regrouping to help Kaylin and Quinten keep score at the place value party in this interactive tutorial.

This is part 1 in five-part series. Click below to view the other tutorials in the series.

Type: Original Student Tutorial

Place Value Party - Part 1:

Mr. Mahoney challenges students to solve 10 less and 10 more problems in a place value party planning adventure in this interactive tutorial.

This is part 1 in five-part series. Click below to view the other tutorials in the series.

Type: Original Student Tutorial

Subtraction with Stanley:

Learn to use place value to solve subtraction problems within 100 in this interactive, basketball-themed tutorial.

Type: Original Student Tutorial

Place Value Party - Part 3:

Find the value of 3-digit numbers which are 10 less with regrouping as Kaylin and Quinten keep score at a place value party in this interactive tutorial.

This is part 1 in five-part series. Click below to view the other tutorials in the series.

Type: Original Student Tutorial

Perspectives Video: Experts

Fluency vs. Automaticity:

How are fluency and automaticity defined? Dr. Lawrence Gray explains fluency and automaticity in the B.E.S.T. mathematics benchmarks in this Expert Perspectives video.

Type: Perspectives Video: Expert

B.E.S.T. Journey:

What roles do exploration, procedural reliability, automaticity, and procedural fluency play in a student's journey through the B.E.S.T. benchmarks? Dr. Lawrence Gray explains the path through the B.E.S.T. mathematics benchmarks in this Expert Perspectives video.

Type: Perspectives Video: Expert

What is Automaticity?:

What does automaticity look like? What is the role of automaticity in mathematics? Dr. Lawrence Gray explores what it means for students to have automaticity with basic mathematics facts in this Expert Perspectives video.

Type: Perspectives Video: Expert

Problem-Solving Tasks

Jamir's Penny Jar:

The purpose of this task is to help students articulate their addition strategies and would be most appropriately used once students have a solid understanding of coin values. This task would be best used in an instructional setting especially since the language is somewhat complex and the teacher might need to help students decode the task statement.

Type: Problem-Solving Task

Comparisons 2:

The purpose of this task if for students to gain a better understanding of <,=,> with the help of number sentences.

</,=,>

Type: Problem-Solving Task

Saving Money 2:

The purpose of this task is for students to relate addition and subtraction problems to money and to situations and goals related to saving money. This task is an instructional task that brings many aspects of the mathematical work that second graders will be doing together with an opportunity to learn about financial literacy concepts.

Type: Problem-Solving Task

One, Ten, and One Hundred More and Less:

This task acts as a bridge between understanding place value and using strategies based on place value for addition and subtraction. Within the classroom context, this activity can be differentiated using numbers that are either simpler or more difficult to manipulate across tens and hundreds.

Type: Problem-Solving Task

Saving Money 1:

The purpose of this task is for students to relate addition and subtraction problems to money and to situations and goals related to saving money. This task has students adding two 2-digit numbers that require regrouping and the solution shows a concrete approach to the solution. This problem can be adjusted based on where students are in their understanding of addition involving two-digit numbers.

Type: Problem-Solving Task

How Many Days Until Summer Vacation?:

The purpose of the task is to allow children an opportunity to subtract a three-digit number including a zero that requires regrouping. The solutions show how students can solve this problem before they have learned the traditional algorithm.

Type: Problem-Solving Task

Tutorials

Subtracting with regrouping:

In this tutorial video from Khan Academy, a subtraction problem is solved which contains two numbers each with two-digits. The video demonstrates subtraction with regrouping using the standard algorithm, as well as a method using expanded form.

Type: Tutorial

Subtracting two-digit numbers without regrouping:

In this video tutorial from Khan Academy, explore subtracting two-digit numbers by using the standard algorithm. This video does not include regrouping.

Type: Tutorial

Adding two-digit numbers without regrouping:

In this tutorial video from Khan Academy, explore adding two-digits numbers with base ten blocks and connect this to the standard algorithm. The examples do not include regrouping.

Type: Tutorial

Understanding place value when subtracting tens:

In this video tutorial from Khan Academy, explore the connection between place value and subtraction. This video explains how to solve a subtraction problem with numbers less than one hundred using base ten blocks.

Type: Tutorial

Understanding place value while adding tens:

Learn how to add 23 + 30 by thinking about place value.

Type: Tutorial

Student Resources

Vetted resources students can use to learn the concepts and skills in this topic.

Original Student Tutorials

Place Value Party - Part 5: 100 Less:

Learn how to create numbers that are 100 less as you wrap up the place value party in this interactive tutorial.

This is part 1 in five-part series. Click below to view the other tutorials in the series.

 

Type: Original Student Tutorial

Place Value Party - Part 4:

Find 100 less and 100 more than a given 3-digit number by helping Kaylin and Quinten keep track of the place value party game points in this interactive tutorial.

 

This is part 1 in five-part series. Click below to view the other tutorials in the series.

Type: Original Student Tutorial

Place Value Party - Part 2:

Find 10 more and 10 less than 3-digit numbers with regrouping to help Kaylin and Quinten keep score at the place value party in this interactive tutorial.

This is part 1 in five-part series. Click below to view the other tutorials in the series.

Type: Original Student Tutorial

Place Value Party - Part 1:

Mr. Mahoney challenges students to solve 10 less and 10 more problems in a place value party planning adventure in this interactive tutorial.

This is part 1 in five-part series. Click below to view the other tutorials in the series.

Type: Original Student Tutorial

Subtraction with Stanley:

Learn to use place value to solve subtraction problems within 100 in this interactive, basketball-themed tutorial.

Type: Original Student Tutorial

Place Value Party - Part 3:

Find the value of 3-digit numbers which are 10 less with regrouping as Kaylin and Quinten keep score at a place value party in this interactive tutorial.

This is part 1 in five-part series. Click below to view the other tutorials in the series.

Type: Original Student Tutorial

Problem-Solving Tasks

Comparisons 2:

The purpose of this task if for students to gain a better understanding of <,=,> with the help of number sentences.

</,=,>

Type: Problem-Solving Task

Saving Money 2:

The purpose of this task is for students to relate addition and subtraction problems to money and to situations and goals related to saving money. This task is an instructional task that brings many aspects of the mathematical work that second graders will be doing together with an opportunity to learn about financial literacy concepts.

Type: Problem-Solving Task

One, Ten, and One Hundred More and Less:

This task acts as a bridge between understanding place value and using strategies based on place value for addition and subtraction. Within the classroom context, this activity can be differentiated using numbers that are either simpler or more difficult to manipulate across tens and hundreds.

Type: Problem-Solving Task

Saving Money 1:

The purpose of this task is for students to relate addition and subtraction problems to money and to situations and goals related to saving money. This task has students adding two 2-digit numbers that require regrouping and the solution shows a concrete approach to the solution. This problem can be adjusted based on where students are in their understanding of addition involving two-digit numbers.

Type: Problem-Solving Task

How Many Days Until Summer Vacation?:

The purpose of the task is to allow children an opportunity to subtract a three-digit number including a zero that requires regrouping. The solutions show how students can solve this problem before they have learned the traditional algorithm.

Type: Problem-Solving Task

Tutorials

Subtracting with regrouping:

In this tutorial video from Khan Academy, a subtraction problem is solved which contains two numbers each with two-digits. The video demonstrates subtraction with regrouping using the standard algorithm, as well as a method using expanded form.

Type: Tutorial

Subtracting two-digit numbers without regrouping:

In this video tutorial from Khan Academy, explore subtracting two-digit numbers by using the standard algorithm. This video does not include regrouping.

Type: Tutorial

Adding two-digit numbers without regrouping:

In this tutorial video from Khan Academy, explore adding two-digits numbers with base ten blocks and connect this to the standard algorithm. The examples do not include regrouping.

Type: Tutorial

Understanding place value when subtracting tens:

In this video tutorial from Khan Academy, explore the connection between place value and subtraction. This video explains how to solve a subtraction problem with numbers less than one hundred using base ten blocks.

Type: Tutorial

Understanding place value while adding tens:

Learn how to add 23 + 30 by thinking about place value.

Type: Tutorial

Parent Resources

Vetted resources caregivers can use to help students learn the concepts and skills in this topic.

Problem-Solving Tasks

Jamir's Penny Jar:

The purpose of this task is to help students articulate their addition strategies and would be most appropriately used once students have a solid understanding of coin values. This task would be best used in an instructional setting especially since the language is somewhat complex and the teacher might need to help students decode the task statement.

Type: Problem-Solving Task

Comparisons 2:

The purpose of this task if for students to gain a better understanding of <,=,> with the help of number sentences.

</,=,>

Type: Problem-Solving Task

Saving Money 2:

The purpose of this task is for students to relate addition and subtraction problems to money and to situations and goals related to saving money. This task is an instructional task that brings many aspects of the mathematical work that second graders will be doing together with an opportunity to learn about financial literacy concepts.

Type: Problem-Solving Task

One, Ten, and One Hundred More and Less:

This task acts as a bridge between understanding place value and using strategies based on place value for addition and subtraction. Within the classroom context, this activity can be differentiated using numbers that are either simpler or more difficult to manipulate across tens and hundreds.

Type: Problem-Solving Task

Saving Money 1:

The purpose of this task is for students to relate addition and subtraction problems to money and to situations and goals related to saving money. This task has students adding two 2-digit numbers that require regrouping and the solution shows a concrete approach to the solution. This problem can be adjusted based on where students are in their understanding of addition involving two-digit numbers.

Type: Problem-Solving Task

How Many Days Until Summer Vacation?:

The purpose of the task is to allow children an opportunity to subtract a three-digit number including a zero that requires regrouping. The solutions show how students can solve this problem before they have learned the traditional algorithm.

Type: Problem-Solving Task

Tutorials

Subtracting with regrouping:

In this tutorial video from Khan Academy, a subtraction problem is solved which contains two numbers each with two-digits. The video demonstrates subtraction with regrouping using the standard algorithm, as well as a method using expanded form.

Type: Tutorial

Subtracting two-digit numbers without regrouping:

In this video tutorial from Khan Academy, explore subtracting two-digit numbers by using the standard algorithm. This video does not include regrouping.

Type: Tutorial

Adding two-digit numbers without regrouping:

In this tutorial video from Khan Academy, explore adding two-digits numbers with base ten blocks and connect this to the standard algorithm. The examples do not include regrouping.

Type: Tutorial

Understanding place value when subtracting tens:

In this video tutorial from Khan Academy, explore the connection between place value and subtraction. This video explains how to solve a subtraction problem with numbers less than one hundred using base ten blocks.

Type: Tutorial

Understanding place value while adding tens:

Learn how to add 23 + 30 by thinking about place value.

Type: Tutorial