How I Use It
One of the best uses of Google Earth is simply navigating students to a particular place that you wish to discuss and allowing them to see that place in its natural setting. The environment surrounding that place or landmark often gives some context clues in regards to certain aspects and allowing students to examine and investigate those for themselves is an important tool.
Although I have experienced some minor difficulties with getting certain places to load correctly (more likely due to internet constraints and not on Google's end), this can be a very handy tool not only to drop in and see a particular landmark or area, but also allow for deeper research and understand for students. Students are much more likely to be engaged if they can interact with the object you are discussing.