If your students learn about faulting, you may want to make yourself a set of these models that illustrate the different types of faults (there are 7 different models available). The US Geologic Society and the National Park Service collaborated to create these easy-to-assemble models. They are simply printed out, then cut out and folded accordingly. There are illustrated instructions to help you with the folding and gluing, but I found it to be pretty self-explanatory. These models are very simple, but they do add a third dimension your fault instruction.