Dynamic Digital Maps offer a variety of options for use in large classroom environments. A Dynamic Digital Map is a stand-alone "presentation manager" computer program that contains text, such as field trip narratives, and analytical data, along with maps, and images and movies. When looking at a geologic or topographic map, the program displays these components by clicks on icons found at appropriate locations. DDMs can be run in "lecture" or lab settings using a computer projector. In these settings, they provide access to geology when the user can’t be there, either because that type of geology isn’t local, or because of bad weather causing trip cancellation. They also provide a rich setting or context for slides (digital images) showing geologic examples and details which can be displayed in class when those topics are introduced. These have been especially effective, when the instructor plays "What if" or "What would you expect" as she shows an image, and then together with students in class, and at their direction, explores options provided by the map setting and other images in the DDM. Examples include looking at picrites, which might be cumulates and examining the idea of mass-balance and fractional crystallization (and looking at olivine in thin section and mineral and major element chemistry), to looking at possible sources for arkoses seen at various map locations. Further, having shown these examples, the instructor can then challenge the students to further expand that context by using the program on their own. DDMs also provide an excellent way, in a class setting, to preview a field trip and thus put in context (both spatially and temporally) the features seen at each stop This is especially useful when dealing with large bus-run field trips of up to 100. They also provide an ideal means for individuals in the class pre- or post-view a field trip at their own leisure. Previews can be especially rewarding if captions for the DDM images contain suggestions of features to examine when visiting the outcrop. For example, when showing an image displaying a dike, you can include the comment that two other cross-cutting relations can be found elsewhere in this outcrop when you visit it. Additional aids to large classroom use include displays of animated cartoons showing processes such as ice retreat and plate-tectonic movements.