World is witness is an internet based project by the US Holocaust Memorial Museum. google earth is used to map the actual places of genocides around the world. On the interactive map, actualisations by the staff of the project and guest contributors can be seen showing eyewitness reports and photos from the places of crisis. Since the beginning of the project, two years ago, several regions have been focussed such as Congo, Chad, Burundi, Rwanda and Sudan, but also Chechnya.
For history teaching the page can be helpful to show the actual dimensions of genocides and to discuss the possibilities of learning from history as well as preventing genocides nowadays. You will find also good resources for lessons about genocides there.