Khan Academy
Khan Academy: Nets of 3d Figures
In this exercise, students practice identifying the 2D nets of 3D figures. Students receive immediate feedback and have the opportunity to get hints and try questions repeatedly.
Khan Academy
Khan Academy: Surface Area Using Nets
In this exercise, students practice finding the surface area using nets. Students receive immediate feedback and have the opportunity to get hints and try questions repeatedly.
Khan Academy
Khan Academy: Surface Area
In this exercise, students practice finding the surface area of 3D objects. Students receive immediate feedback and have the opportunity to get hints and try questions repeatedly.
Wolfram Research
Wolfram Math World: Surface Area
A good site explaining surface area. Scroll down the page for quick references to surface area formulas for fundamental geometric objects. The site has links to related topics.