This resource presents an internet directory of resources for Java programmers.

Finally, an interactive Sketchpad for geometry that is free! Students are able to understand various theorems, definitions, and objects through observations and explorations using an interactive applet.

An interactive Java applet which allows the user to investigate the path of light through a lens shape object. The shape of the object, the index of refraction of the material, and the location of the incident rays can be altered.

Chinese-language Java applet illustrating Fermat's principle that light follows the fastest path between any two points. Excellent animation and accompanying text. Relates Fermat's principle to Snell's law.

An interactive Java applet game in which the reflection of light is compared to the path of a billiard ball. Users view images of a target ball and try to direct a cue ball in such a manner as to hit it.

A Java applet which allows the user to emulate a refracting telescope and a light microscope. This is a great site to get information on the subject and better understand it through diagrams and charts.

A Java applet which allows the user to emulate a refracting telescope and a light microscope. This is a great site to get information on the subject and better understand it through diagrams and charts.

The interactive applet allows learners to explore the relationships between side length, area, and perimeter. Students see how changes in the scale factor influence the ratio of areas and perimeters. [Requires Java.]