Online Universities has provided a list of 100 educational virtual tours. With topics such as:

• Cities (including Pompeii and Ancient Rome)
• Famous landmarks and buildings (including Stonehenge, Taj Mahal and the Vatican)
• Museums (including the Louvre and the Smithsonian)
• Outer space
• How things are made (Toyota cars and Hershey chocolate)
• Humans and animals
• Google Earth virtual tours (Cathedrals, castles, palaces, libraries and universities) – note that you need to have Google Earth installed on your computer

There are lots of tours to choose from. Well worth a look.