The Nebraska Astronomy Applet Project provides online laboratories targeting the introductory astronomy audience. Each lab consists of background materials and one or more simulators that students use as they work through an accompanying lab guide. The modules also provide background information, pedagogical objectives, pretests and post-tests. Topics include content which is typically covered in a one-year high school astronomy course or a one-semester undergraduate course in introductory astronomy. The applets simulate important phenomena such as basic coordinates and seasons, the rotating sky, planetary orbits, lunar phases, binary eclipses, stellar evolution, and more.