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Lesson Plans and Worksheets for Grade 3
Lesson Plans and Worksheets for all Grades

Videos, examples, solutions, and lessons to help Grade 3 students learn to use multiplication and division within 100 to solve word problems in situations involving equal groups, arrays, and measurement quantities, e.g., by using drawings and equations with a symbol for the unknown number to represent the problem.

Common Core: 3.OA.3

### Suggested Learning Target

• I can determine when to multiply and divide in word problems.
• I can represent multiplication and division word problems using drawings, and equations with unknowns in all positions.
Unknown Product
Equal Groups
- There are 3 bags with 6 plums in each bag. How many plums are there in all?
Equal Groups (Measurement) - You need 3 lengths of string, each 6 inches long. How much string will you need altogether?
Array - There are 3 rows of apples with 6 apples in each row. How many apples are there?
Area - What is the area of a 3 cm by 6 cm rectangle?
Compare - A blue hat costs \$6. A red hat costs 3 times as much as the blue hat. How much does the red hat cost?
Compare (Measurement) - A rubber band is 6 cm long. How long will the rubber band be when it is stretched to be 3 times as long?

3 × 6 = ?

Group Size Unknown
Equal Groups
- If 18 plums are shared equally into 3 bags, then how many plums will be in each bag?
Equal Groups (Measurement) - You have 18 inches of string, which you will cut into 3 equal pieces. How long will each piece of string be?
Array - If 18 apples are arranged into 3 equal rows, how many apples will be in each row?
Area - A rectangle has area 18 square centimeters. If one side is 3 cm long, how long is the side next to it?
Compare - A red hat costs \$18 and that is 3 times as much as a blue hat costs. How much does a blue hat cost?
Compare (Measurement) - A rubber band is stretched to be 18 cm long and that is 3 times as long as it was at first. How long was the rubber band at first?

3 × ? = 18
18 ÷ 3 = ?

Number of Groups Unknown
Equal Groups
- If 18 plums are packed 6 to a bag, then how many bags are needed?
Equal Groups (Measurement) - You have 18 inches of string, which you will cut into pieces that are 6 inches long. How many pieces of string will you have?
Array - If 18 apples are arranged in equal rows of 6 apples, how many rows will there be?
Area - A rectangle has area 18 square centimeters. If one side is 6 cm long, how long is the side next to it?
Compare - A red hat costs \$18 and a blue hat costs \$6. How many times as much does the red hat cost as the blue hat?
Compare (Measurement) - A rubber band was 6 cm long at first. Now it is stretched to be 18 cm long. How many times as long is the rubber band now as it was at first?

? × 6 = 18
18 ÷ 6 =

### Multiplication Word Problems

Multiplying Using Groups
2 × 3 means 2 groups of 3
3 × 2 means 3 groups of 2
Example:
5 girls each check out 3 books at the library. Write the multiplication equation that represents this situation. Understand multiplication problems using equal groups
One way to solve multiplication facts is by making equal groups. Equal groups is creating groups withe the same number of pieces in each group.
When solving equal groups, count the number of groups first, then count the pieces in each group.
The multiplication sentence shows the number of groups first and the number of pieces in each group.
The total number of piece is called the product. It is the answer to the problem. Solving Multiplication Facts with Arrays
In this lesson, you will learn how to solve multiplication problems by creating an array.
Multiplication is combining equal groups of objects.
An array shows equal groups of rows and columns.
When solving an array, count the rows first, then count the pieces in each row.
The multiplication sentence shows the rows first and the pieces in each row. Learning to Multiply using Multiplication Strategies
Multiplication is combining equal groups together.
The parts of a multiplication sentence are factors and the product.
Four strategies to help with multiplication are:
• Arrays
• Equal Groups
• Number lines

Multiplication with Bar Models
The second graders collect 65 books for the book drive. They put some of the books in boxes and have 25 books left to pack. The third graders have four times as many books in boxes. There are none left to pack. How many books did the third graders collect?

### Writing Division Equations to Solve Word Problems: 3.OA.3

Learn the parts of a division equation and how division relates to multiplication in order to write and solve a division word problem.
Examples:
1. Evan is making spaghetti and meatballs for his friends. He makes 30 meatballs. He wants 5 meatballs in each plate of spaghetti. How many plates can Evan make?
2. Kevin is making sandwiches. He has 16 slices of bread. He needs 2 slices of bread for each sandwich. How many sandwiches can Kevin build? Build and equation to represent this problem.

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.