1. 5-Minute Check
Find the perimeter of a rectangle that has a length of 12 feet and a width of 3 feet.
Find the perimeter of a square whose length is 9 yards.

2. Measurement: Area
By Mr. Bales

3. Objective
By the end of the lesson, you will be able to find the area of rectangles and squares.
Standard 4MG1.4 - Students will understand and use formulas to solve problems involving….areas of rectangles and squares.
Standard 4MG1.1 - Students will measure the area of rectangular shapes by using appropriate units, such as square centimeters, square meter, square kilometer, square inch, square yard, or square mile.

4. Introduce
Using 16 base-ten block units with a partner, I want you to make different types of rectangles using all 16 units.
For example, I could have 1 row of 16 units as one rectangle.
Please write down all the different ways you and your partner come up with.
What lengths and widths can you use to make a rectangle with 16 units?

5. Teach
What is the similarity between the length and width of a square block?
Which of your models showed a square made from the 16 blocks?
How is a rectangle that measures 2 units by 8 units the same as one that measure 8 units by 2 units?
How are the two rectangles different?

6. Hu Family
The Hu family wants to put the sandbox shown in their backyard.
What is the area of the sandbox?
10 ft
5 ft

7. Area
Area is the number of square units needed to cover a region or figure without any overlap. It is measured in square units.

8. Area of a Rectangle Another Way: Multiply
Sandbox - Find the area of the sandbox.
One Way: Count
There are 50 squares
Another Way: Multiply
Multiply the length times the width to find the area.
A = length x width
A = l x w
A = 10 ft x 5 ft
A = 50 square feet
10 ft
5 ft

9. Area of a Rectangle
To find the area of a rectangle, multiply the length by the width.
A = l x w w l l

10. Area of a Square
To find the area of a square, multiply the length of one side s by itself.
A = s x s s

11. Area of a Square
What is the area of the picture if its sides are all 4 inches in length?
A = side x side
A = 4 in x 4 in
A = 16 square inches
The area of the picture is 16 square inches.
Watch Mrs. Benson explain: Mrs. Benson!!
4 in.

12. Bales Bucks!!

13. Assignment
Page #’s
Get them all correct, No Math Homework