CK-12 Foundation
Ck 12: Interactive Geometry: 1.11 Surface Area and Nets
Explore surface areas and nets with 2D and 3D shapes.
Illustrative Mathematics
Illustrative Mathematics: 8.g Circle Sandwich
Eighth graders are presented with a drawing of a large square inscribed by a circle which is itself inscribed by a second square. They are asked to find the area of the circle outside the smaller square and compare it to the area of the...
PBS
Pbs: Geometry and Classification of 2 D Figures: Bianca Busts a Move
In this video from Cyberchase, Bianca breaks her friend's tabletop when she's practicing dance moves in his living room. She uses measurement and geometry to get a new piece of wood that will fit the table exactly. The accompanying...
Illustrative Mathematics
Illustrative Mathematics: 7.g Eight Circles
In this lesson plan, 7th graders use their knowledge of formulas to determine the area and circumference of a circle.