Area and circumference of a circle often gives our students their first taste of geometry during the year. Also, it seems like students see formulas for the first time when learning this topic. Usually, they don’t come to us understanding how to plug values into formulas. That means that we have to teach the idea of using formulas to them as well as how to find the area and circumference of a circle. Even though that can feel daunting, though, the great thing about circles and geometry is that they lend themselves to application pretty easily. We definitely have the opportunity to let students see area and circumference in a hands-on way. This post is full of engaging, fun area and circumference activities for secondary math students. [Read more…] about 10 Activities for Finding Area and Circumference of a Circle

# circles

## Teaching Area and Circumference of Circles through Discovery

A highlight in my math class during this past month was teaching area and circumference of a circle. I’m excited to share with you a twist on the traditional teaching of this topic that made a huge difference for my students. One thing that has thrown my students for a loop in previous years was getting the area and circumference of a circle mixed up. Over the unit I often heard this chorus of questions: What was that formula again? 2 pi r squared? Which one is this again- circumference or area? When do I have to square the unit?

So, this year I wanted to start off by preemptively addressing those common misconceptions. How did I do that? By building students’ conceptual knowledge before we ever talked about formulas and calculations. I started with a discovery lab approach to get them to explore circles. (I’ve talked about the discovery lab approach before here). They would draw conclusions and build their understanding before using any formulas to solve problems. And as we near the end of the unit, I haven’t heard the same questions that were so common last year. Hooray! [Read more…] about Teaching Area and Circumference of Circles through Discovery