Yes Sir I have used Google Earth and it is indeed very useful.When you first load GE you have a wealth of information available at your fingertips. Thousands of aerial and satellite photos, dozens of layers of information: city names, country borders, airport locations, photos, road maps, National Geographic content, volcanoes, and more. Since Google Earth is an intuitive and fun tool, I believe you could use it as a visualization and educational tool for almost any subject. Once students prepare their own content, GE can be used to present their work - or even share their work with the world.Google has their own site on educational uses for Google Earth.Google Earth is a powerful visual tool for visualizing and presenting information tied to location. And now, with Google Earth 4.2 there are even more reasons to use GE in education (GE 4.2 adds the new Sky mode which is wonderful for astronomy lessons, the flight simulator mode for teaching about aviation, and a wealth of new features
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I use both google earth & wikimapia. G-earth is a good tool, however, I;ve seen many maps are not updated. I saw a friend's home in Chennai, pinpointed the location precisely, but there is no appartment complex in G-earth screen, only a barren plot of green land.
But for locating most major landmarks and just exploring cities, G-earth is great! I mean where else can u see what's cooking over @ North Korea sitting in Palakkad?