Circumference and Area

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Objective

SWBAT calculate the circumference and area of circles

Big Idea

What’s the difference between circumference and area?

Launch

5 minutes
  • POD

As students enter the room, they will have a seat, take out their Problem of the Day (POD) sheet and begin to work on the question on the SMARTboard. The POD allows students to use MP 3 continually based on the discussions we have about the problem each day.

  • Learning Target

The target for the day is also on the SMARTboard each day when students enter the room.  The target for today’s lesson is for students to calculate the circumference and area of a circle.

To start class we will review the relationship between area and diameter and radius. Do students understand that the radius is half of the diameter? Do they understand the relationship between the circumference and pi? The POD will generate discussions where I can find the answers to these questions.

Find the radius and the circumference of a circle with a diameter of 10 cm.

Explore

30 minutes

We will walk through a SMART notebook that builds upon the introduction to finding the circumference of a circle that we did in the previous class. Students will review the vocabulary then work through practice problems using radius and diameter to find the circumference. Students will also look at finding the area of circles. We will need to discuss what area means and how area is related to circumference. I would like students to discover a means to remember the formula for both area and circumference to avoid any application of the incorrect formula in a problem-solving situation.

Landing

5 minutes

To wrap up the class, the exit ticket will be an opinion-gathering question for students to provide some feedback on their understanding. I want to know if they understand the difference between finding the area and finding the circumference. This formative information can help me decide if we need intervention on circumference or area or if we can move on because they understand.