Standard 1 : Represent and solve problems involving addition and subtraction. (Major Cluster) (Archived)



This document was generated on CPALMS - www.cpalms.org


Clusters should not be sorted from Major to Supporting and then taught in that order. To do so would strip the coherence of the mathematical ideas and miss the opportunity to enhance the major work of the grade with the supporting clusters.

General Information

Number: MAFS.2.OA.1
Title: Represent and solve problems involving addition and subtraction. (Major Cluster)
Type: Cluster
Subject: Mathematics - Archived
Grade: 2
Domain-Subdomain: Operations and Algebraic Thinking

Related Standards

This cluster includes the following benchmarks
Code Description
MAFS.2.OA.1.1: 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.
MAFS.2.OA.1.a: Determine the unknown whole number in an equation relating four or more whole numbers. For example, determine the unknown number that makes the equation true in the equations 37 + 10 + 10 = ______ + 18, ? – 6 = 13 – 4, and 15 – 9 = 6 + square box.


Related Access Points

This cluster includes the following access points.

Access Points

Access Point Number Access Point Title
MAFS.2.OA.1.AP.1a: Solve addition and subtraction word problems within 100 using objects, drawings, or pictures.
MAFS.2.OA.1.AP.1b: Use pictures, drawings or objects to represent the steps of a problem.
MAFS.2.OA.1.AP.1c: Write or select an equation representing the problems and its solution.
MAFS.2.OA.1.AP.bb: Determine the unknown whole number in an equation relating four or more whole numbers. For example, determine the unknown number that makes the equation true in the equations 37 + 10 + 10 = ______ + 18, ? – 6 = 13 – 4, and 15 – 9 = 6 + .
MAFS.2.OA.1.AP.aa: Find the unknown number in an equation (+, - ).


Related Resources

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

Original Student Tutorial

Name Description
Balancing Act:

Help Tyler balance equations by finding the unknown number in this interactive tutorial.

Formative Assessments

Name Description
What Number Makes the Equation True?:

Students find the missing number in an equation relating four whole numbers.

Relating Four Whole Numbers:

Students find the missing number in an equation relating four whole numbers that involves addition and subtraction.

Determine the Missing Addend:

Students find the missing addend in an addition equation relating five whole numbers.

Compare (Bigger Unknown) Word Problems:

Students are asked to solve two Compare (Bigger Unknown) word problems: one involving the word more and one involving the word fewer.

Solving a Two-Step Word Problem: Eating Grapes:

Students are asked to solve a two-step word problem that combines a Compare (Bigger Unknown) problem and a Compare (Smaller Unknown) problem.

Compare (Smaller Unknown) Word Problems:

Students are asked to solve two Compare (Smaller Unknown) word problems: one involving the word more and one involving the word fewer.

Solving a Two-Step Word Problem: Marbles in a Bag:

Students are asked to solve a two-step word problem that combines a Put Together (Result Unknown) problem and a Take From (Result Unknown) problem.

Word Problems with Result Unknown:

Students are asked to solve three word problems: Add To (Result Unknown), Take From (Result Unknown), and Put Together/Take Apart (Total Unknown).

Solving a Two-Step Word Problem: Going Fishing:

Students are asked to solve a two-step word problem that combines an Add To (Result Unknown) problem and a Compare (Difference Unknown) problem.

One, Two, Three Problems to Solve:

Students are asked to solve three word problems: Put Together (Addend Unknown), Take From (Change Unknown), Add to (Change Unknown).

How Many More and How Many Fewer?:

Students are asked to solve two Compare (Difference Unknown) word problems: a how many more and a how many fewer variation.

Both Addends Unknown:

Students are asked to solve a Put Together/Take Apart (Both Addends Unknown) word problem and explain their strategies.

Add To and Take From (Start Unknown):

Students are asked to solve two word problems: Add To (Start Unknown) and Take From (Start Unknown).

Lesson Plans

Name Description
Determine the Unknown in an Equation:

Students will apply their understanding of the equal sign as a relational symbol to determine the unknown number in equations relating four whole numbers. Students are encouraged to explore a variety of strategies for equations with addition or subtraction on each side of the equal sign.

The Mystery Of The Missing Number:

In this lesson, students will find the “mystery” (missing) number in an addition or subtraction equation relating 4 whole numbers with the unknown in any position. Students will complete an activity in partners, using hint cards as needed.

Word Problems Galore!:

This lesson contains multiple word problems from various situation types. Different numbers for each problem are given based on student need.

Into the Unknown:

In this lesson, the teacher will introduce using base ten blocks to solve addition equations relating 4 whole numbers with the unknown in any position. Students are given the opportunity to practice with a partner. The students will be engaged with manipulatives, teacher questioning, and partner practice as they determine the unknown number.

Table Top Problem:

In this Model Eliciting Activity, MEA, The Junior League needs the students' help to determine which table rental company to use for their Charity Auction. With a tight budget, limited time, and a mistake in the order, students must create a procedure for determining the best rental company, 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. 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

Sweet Donut Shop:

In this Model Eliciting Activity, MEA, students will help the Sweet Donut Shop determine what the newest donut will be. Students are given the cost to make each batch along with the selling price and are asked to determine the profit for each batch. Students create a procedure for ranking the donuts and write a letter explaining the procedure and the ranking. In the “twist” students are provided the starting and finishing times for each batch. They must determine the total amount of time, decide if their procedure should change based on the new information, and write a letter explaining whether the procedure changed and the new ranking of the donuts.

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

Words and Subtraction:

In this lesson, students will build on their earlier work of representing and solving situational problems (result unknown, change unknown, start unknown). Students will use related equations or drawings.

Let's Do Some Solving:

In this lesson students will solve one-step addition word problems using base ten blocks, hundred charts, drawings, or strategies based on place value and/or the relationship between addition and subtraction.

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.

Are Your Numbers Equal to My Numbers?:

This is a lesson that reinforces the meaning of the equal sign while students determine the unknown whole number in an addition equation.

Amazing Animal Athletes (Addition and Subtraction Story Problems):

In this lesson, students will be able to solve one and two step word problems using addition and subtraction to compare human and animal athletic abilities. This lesson focuses on identifying the information given, comparing numbers, and identifying the missing information needed to solve the word problem using either addition or subtraction.

Kelly's Jelly:

Students use problem solving skills, data sets presented in a chart, two and three digit addition, writing skills and money skills to determine which brand of jelly beans they would like to purchase. The jelly beans differ in taste, quantity, and cost. The students must then check their procedure to determine if it will work when given an additional piece of 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. Click here to learn more about MEAs and how they can transform your classroom.

Ten-Hut! Part-2 (Subtraction):

This fun, kinesthetic lesson allows students to gain insight into how to use place value when subtracting a one-digit number from a two-digit number. The focus is on students using their bodies, as well as math manipulatives, to solve subtraction problems within 100 that do not require regrouping.

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.

Problem-Solving Tasks

Name Description
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.

A Pencil and a Sticker:

The purpose of this task is to represent and solve problems involving addition and subtraction with the help of a bar diagram.

Professional Development

Name Description
Johnnie’s Cars - Using Direct Modeling and Counting Strategies to Solve Addition and Subtraction Story Problem Types:

This tutorial will help teachers identify the action in story problems as joining or separating, as well as the direct modeling and counting strategies used by your students to think about and solve them.

Teaching Idea

Name Description
Shamu Math-SeaWorld Classroom Activity: In this activity, the students demonstrate that numbers can be used to describe various quantities and relationships between quantities. Students gain experience adding, subtracting, multiplying, and dividing - building their understanding of how numbers are put together and taken apart. Students connect what they know to symbolic representation using number sentences.

Tutorials

Name Description
Understanding the Meaning of the Equal Sign:

In this tutorial, you will learn more about what the equals sign means and how to balance equations.

Solving a word problem using the standard algorithm for subtraction:

In this video tutorial from Khan Academy called "losing tennis balls", explore solving a two-step subtraction word problem using the standard algorithm.

Adding two-digit numbers using the standard algorithm:

In this tutorial video from Khan Academy, called "Fence posts for horses", explore adding a two digit number to a two digit number using the standard algorithm

Adding and subtracting on number line word problems:

In this video tutorial from Khan Academy, explore using a number line solve word problems involving more than two numbers.

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.

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.



Student Resources

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

Original Student Tutorial

Title Description
Balancing Act:

Help Tyler balance equations by finding the unknown number in this interactive tutorial.

Problem-Solving Tasks

Title Description
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.

A Pencil and a Sticker:

The purpose of this task is to represent and solve problems involving addition and subtraction with the help of a bar diagram.

Tutorials

Title Description
Understanding the Meaning of the Equal Sign:

In this tutorial, you will learn more about what the equals sign means and how to balance equations.

Solving a word problem using the standard algorithm for subtraction:

In this video tutorial from Khan Academy called "losing tennis balls", explore solving a two-step subtraction word problem using the standard algorithm.

Adding two-digit numbers using the standard algorithm:

In this tutorial video from Khan Academy, called "Fence posts for horses", explore adding a two digit number to a two digit number using the standard algorithm

Adding and subtracting on number line word problems:

In this video tutorial from Khan Academy, explore using a number line solve word problems involving more than two numbers.

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.

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.



Parent Resources

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

Problem-Solving Tasks

Title Description
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.

A Pencil and a Sticker:

The purpose of this task is to represent and solve problems involving addition and subtraction with the help of a bar diagram.

Tutorials

Title Description
Solving a word problem using the standard algorithm for subtraction:

In this video tutorial from Khan Academy called "losing tennis balls", explore solving a two-step subtraction word problem using the standard algorithm.

Adding two-digit numbers using the standard algorithm:

In this tutorial video from Khan Academy, called "Fence posts for horses", explore adding a two digit number to a two digit number using the standard algorithm

Adding and subtracting on number line word problems:

In this video tutorial from Khan Academy, explore using a number line solve word problems involving more than two numbers.

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.

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.