Google Earth just keeps getting better and better! Approximately a year or so ago, they introduced streetside maps that allow you to see the view from street level. If you haven't been in recently, check out the 360 feature (a red dot with the number 360 in the middle of it). You can turn it on by opening "Layers>Gallery>360 cities." Typically, you'll see these panoramics in major cities at tourist attractions.
When you click on the 360 button, you'll see a 360 panoramic image, clear as a bell. What amazed me about the 360 pictures is how they capture a full scene from the perspective of an individual. So imagine you are standing on a street in Tulum, Mexico. You'll see the taco stand, individuals riding by on bikes, cars, tourists on the streets, people eating in restaurants. It feels like you are there. These great images are hosted by 360 Cities and imported into Google Earth, see the shot above at http://360cities.net/image/carnitas-merchant
For teaching anything related to history, geography, study of cultures, etc. this tool is wonderful! When the 360 view is open, you can do a "File>save" and create a .jpg of that image. These images can be imported into slideshows or other rich media that students create for reports or projects.
Oh, and have you seen Ancient Rome in 3D in Google Earth?! Check out this first ancient city available in Google Earth, inside the Layers>Gallery menu! Note the ancient Rome curriculum competition, due February 2009.