LOVE this!! Google launched the Expeditions Pioneer Program in September, free to schools, to let educators lead students on virtual field trips to over 100 far flung locales like Mars and the Great Wall of China. The Google Expedition teams have been setting up the program for teachers at selected schools around the world. So far, over 500K students have taken these immersive VR field trips. The newest Expedition is to Buckingham Palace (thru a partnership with the Royal Collection Trust). The Palace also produced a YouTube 360 video, so anyone with a smartphone (or Web browser) can take a private tour with the paintings curator BUT it only really works well if you use Google Cardboard.
Google has also just launched a free beta version of the Expeditions app for select schools that sign up to participate.