Videos and songs to help Grade 2 students learn how to 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.

Common Core: 2.OA.1

- I can choose when to use addition and/or subtraction in a word problem
- I can represent addition and subtraction word problems using objects, drawings, and equations with unknowns in all positions.
- I can solve addition and subtraction word problems that involve two steps (doing one computation, and using that answer to perform a second computation that leads to the solution of the problem).
- I can solve word problems with unknown numbers in different positions (e.g., 5 + ? = 13, ? + 8 = 12)
- I can explore addition and subtraction with manipulatives (e.g., snap cubes, subitizing cards, tens frames, hundreds charts, number lines and empty number lines)
- I can take apart and combine numbers in a wide variety of ways
- I can use >, =, and < when comparing quantities
- I can use different thinking strategies to develop the understanding of the traditional algorithms and their processes
- I can apply properties of addition and subtraction
- I can choose the most efficient strategy to solve a problem
- I can solve various types of addition and subtraction word problems
- I can use _ or ? to represent an unknown in an equation

Related Topics:

More Lessons for Grade 2

Common Core for Grade 2

**Take Apart and Combine Numbers**

**Total Unknown**

Three red apples and two green apples are on the table. How many
apples are on the table?

3 + 2 = ?

**Addend Unknown**

Five apples are on the table. Three are red and the rest are
green. How many apples are green?

3 + ? = 5, 5 3 = ?

**Both Addends Unknown**

Jenny has five flowers. How many can she put in her red vase and
how many in her blue vase?

5 = 0 + 5, 5 = 5 + 0

5 = 1 + 4, 5 = 4 + 1

5 = 2 + 3, 5 = 3 + 2

**Compare Word Problems
Difference Unknown**

(How many more? version):

Jane has two oranges. Mary has five oranges. How many more oranges does Mary have than Jane?

2 + ? = 5

(How many fewer? version):

Jane has two oranges. Mary has five oranges. How many fewer oranges does Jane have than Mary?

5 2 = ?

(Version with more):

Mary has three more oranges than Jane. Jane has two oranges. How many oranges does Mary have?

2 + 3 = ?

(Version with fewer):

Jane has 3 fewer oranges than Mary. Jane has two oranges. How many oranges does Mary have?

3 + 2 = ?

(Version with more):

Mary has three more oranges than Jane. Mary has five oranges. How many oranges does Jane have?

5 3 = ?

(Version with fewer):

Jane has 3 fewer oranges than Mary. Mary has five oranges. How many oranges does Jane have?

? + 3 = 5

One-Step Word Problems 1 - Bar Model (Part-Whole)

An effective model always has a visual model of the problem, a number sentence, and the answer to the question in a complete sentence.

Mr. Oliver had 88 pencils. He sold 27 of them. How many pencils did he have left?

Word Problems 2 - Bar Model (Part-Whole)

This video employs a visual way to solve world problems using bar modeling. This type of word problem uses the part-whole model. Because the part is missing, this is a subtraction problem.

There are 98 hats. 20 of them are pink and the rest are yellow. How many yellow hats are there?

Word Problems 3 - Bar Model (Part-Whole)

This video employs a visual way to solve world problems using bar modeling. This type of word problem uses the part-whole model. Because the whole is missing, this is an addition problem.

Example:

Mr. Gray sold 54 drinks in the morning. Mr. Frank sold 25 drinks at night. How many drinks did they sll altogether?

Part-whole Word Problem

This video shows you how to solve a word problem using bar models. This technique is one of the strategies that can be used to address Common Core math standard 2.OA.1.

Example:

Maya had some stamps. She gave 7 stamps to her younger brothers. Maya then had 14 stamps. How many stamps did Maya have at first?.

Comparison Word Problem

This video explains how to use bar modeling in Singapore math to solve word problems that deal with comparing. Example:

Example:

Adam has 11 fewer lollipops than Hope. If Adam has 16 lollipops, how may lollipops does Hope have?

Bar Model (Comparison)

This video employs a visual way to solve world problems using bar modeling. This type of word problem uses the comparison model. Because the part is missing, this is a subtraction problem.Â

Example:

Cayla did 88 sit-ups in the morning. Nekira did 32 sit-ups at night. How many more sit-ups did Cayla do than Nekira?

Two-Step word problems

This video shows you how to solve two-step word problems using bar models.

Example:

50 children attended the birthday party. 13 children left during the first hour. 9 children came in during the second hour. How many children were at the birtday party then?

Rotate to landscape screen format on a mobile phone or small tablet to use the **Mathway** widget, a free math problem solver that **answers your questions with step-by-step explanations**.

You can use the free Mathway calculator and problem solver below to practice Algebra or other math topics. Try the given examples, or type in your own problem and check your answer with the step-by-step explanations.