DR Xargle's Book of Earth Mobiles

Dr Xargle, the alien schoolmaster, is now teaching his class about earthling modes of transport. He starts with the oldest form of all (the Dobbin: grab his hairdo and fling your legs in the air), continues through wheels great and small, before arriving at boats (made from a tree and a sheet tied to a stick with a string), planes (they have a tail, some wings and a beak, but no feathers) and trains.
And the class trip for this lesson? A genuine ride on a Ghost Train. That should set them up nicely!