If you're preparing to teach Bridges Grade 3, Unit 8 on bridges, you might want to view the 15 Longest Bridges in the World. (Due to advertising on the page, preview before sharing with your class.) Students will find it hard to believe that bridges can be over 100 miles long! Pose some questions:
Looking for ways to explore relationships between circumference, radius, diameter and area? Check out The Circle Tool from NCTM Illuminations. You’ll notice three buttons that run along the top of the game window: Intro, Investigation and Problems. With the Intro button selected, you’ll notice an icon of a video camera.