Your students have been developing their understanding of radius, diameter, and circumference over the last three lessons. Now let’s invite them to put them all together.
On the warm-up, we ask students to think about the relationship between the perimeter of a circle and a semicircle. While on this screen, we hope you’ll find some students who think that the semicircle has half the perimeter of the circle. What can you do with that idea so that a) those students will feel affirmed as thoughtful mathematicians and b) you can help them develop that idea further?
Tell me about a different world.
When you ask a question and a student answers incorrectly, it's often helpful to realize that they're answering a different question correctly.
At some point in your discussion of the warm-up, consider telling your class, “Half is the wrong answer to this question, but it’s the right answer to a different question. What question might that be?”
By asking your class that question, you might:
Give students who answered the original question correctly more math to think about.
Celebrate students who were incorrect for the mathematical sense they were making.
Help all of your students make an important connection between perimeter and area.
All this, just by asking students to tell you about a different world!
Happy math-ing!
Dan & the Desmos Classroom Team
PS. Please give us feedback on the last lesson.
Use the feedback form or just click your answer below then click "Submit" on the form!
How likely is it that you would recommend this lesson to a friend or colleague?
.png?width=1200&height=120&upscale=true&name=DM_Logo_6-A1%20(1).png "DM_Logo_6-A1 (1)"){kind=logo}
