An interactive applet and associated web page that demonstrates how to calculate the surface area of a cylinder. A cylinder is shown where the height and radius can both be changed by dragging. The volume is continuously recalculated as you drag. The calculations can be turned off for class discussion.

The web page has the formula for the area calculation, and a second applet that shows how a cylinder can be "unrolled" to show the components in the calculation.

Applet can be enlarged to full screen size for use with a classroom projector. After use in the classroom, student can access it again from any web browser at home or in the library with no login required.

This resource is a component of the Math Open Reference Interactive Geometry textbook project at http://www.mathopenref.com.