See "Maker Movement", 2005-1018.

Here's a practice factory that GM operates to train new employees to work on an assembly line.[1] There are plywood mockups of cars rolling on conveyors, and the new employees bolt things on.

A useful lesson for kids to get is how you make a hundred of something. The difference between making one and making many is not something most people get. Make something on a 3D printer. Then, for comparison, make a mold, and resin cast a batch of them.

[1] https://www.youtube.com/watch?v=b12sOQ2hOF4