What's My Area?
Students will be able to solve for the area of a rectangle or square.
- Bring the students to the class meeting area.
- Draw a rectangle on the board.
- Ask students to talk about the shape they see and what they know about it. Listen for students to use key terms such as area, length, and width.
Explicit Instruction/Teacher modeling(10 minutes)
- Tell the students that today, they're going to learn about solving for the area of a rectangle or square.
- Let the students know the area of a rectangle or square is the space or the surface area inside the shape.
- On the board, write the word "area" next to or underneath the shape drawn. Tell students that the area of a rectangle or square is generally represented with a capital "A."
- Let them know that the formula for determining the area of a rectangle or square is A = L x W, whereby, A = area, L = length (vertical, up and down), and W = width (horizontal, side-to-side).
- On the board, surrounding the shape drawn, place the letter “l” along each side representing the length of the shape drawn. Then, place a “w” along each side representing the width of the shape drawn.
- Direct the students’ attention to the board.
- Draw a rectangle or square. Label the length (L) as 8 inches and the width as 6 inches.
- Write the formula shared previously for area using the information correlating to this shape: A = 8 inches x 6 inches.
- Let the students know that based on our formula, the area of our shape is A = 42 inches.
- Tell them that we are not done yet. Let them know that the area of a figure is represented in square units.
- In the case of a rectangle or square, area has to be expressed in square units. Thus, the area of our shape is 42 square inches.
Guided Practice(15 minutes)
- Put a few more (2-4) rectangle or squares on the board.
- Place a length and width on the side of the first one.
- Ask for volunteers to raise their hands and share with the class the area (A) of the first shape.
- Have them justify or share how they came up with their answers in the form of an equation.
- Continue until you have found the area for all the shapes drawn.
- You may try giving the area of a figure and withholding either the length or the width. For example: 54 square inches = 9 inches x ___ inches. The student is solving for the Length (l) of the shape, not the area.
Independent working time(15 minutes)
- Send the students back to their seats.
- Give them 8-10 problems on the board.
- Walk around and observe the students as they work on completing the assignment.
- Monitor the students as they work, making sure the problems are done correctly, in that they are justifying their answers by showing their work in coming up with the area for each figure.
- During this time, ask questions of the students to make sure they understand the concept of area.
- Answer questions by the students to help them clarify any misconceptions.
- Give advanced students problems missing the length or width. Have them solve for the length or the width of a shape.
- Observe and monitor struggling students more closely. Get involved in helping them write equations to solve for different areas. If remediation is required in the area of multiplication, you might want to do a review of the strategies involved in solving a multiplication problem.
A laptop, document camera, projector, and/or interactive whiteboard may be used during the lesson to visually enhance the students' learning.
- Assess the students based on their comments and feedback.
- Also assess them based on their answers to the assigned problems.
- Give each student an index card and have them choose a question for which to create a written response:
- What information do you need in order to find the area of a rectangle or square?
- What did you notice is different about finding the area of a square and the area of a rectangle? What is the same?
- How do you find the area of a rectangle or square?
Review and closing(10 minutes)
- Bring students back to a common area in the classroom to review the answers to the independent work. Call on volunteers to share their answers and how they arrived
- Instruct the rest of the class to give a thumbs up/down if they agree/disagree with their peer's answer. Then, call on a nonvolunteer to explain why they agree/disagree.