During the agricultural era, when most people worked on farms, a father would teach his son how to till the land, plant grain, and harvest crops. The son learned the proper techniques for irrigating, thinning, and weeding for a more plentiful yield. Later, the son would pass the knowledge he acquired on to his own children.
Now, for the first time in history, multiple generations sit together in the classroom. And it's not always the older generation teaching younger colleagues. How do lear