In 1958, I was teaching Junior High School Science in Campbell, CA.  As one of the kid's science projects, I had 5 classes, about 150 students, build air bearings with the help of those students also taking wood shop.  No giant theories here, just kids having fun and learning something on the way.  Here's what they did:

And now, off to the air bearing races.  Our classroom had a linoleum floor.  We pushed the chairs aside.  In groups of 8, they blew up their balloons and stretched the balloon necks over the protruding dowel (while keeping the filled balloon pinched shut.)  They lined up at one side of the room, and, on a signal, released the air into the disc and flicked the disc's edge, driving it toward the other side of the room.  Greatest distance achieved was the winner.  Concept learned:  air can be a lubricant, a very good one.