I've been reading up on using some sort of a $.50 hex buffer in order to shield the board from power fluctuations, short circuits and other newbie mistakes. Seems like a great idea! In fact, I wonder why it's not routinely done, at the entry level at least; but I must be missing something. What are the disadvantages to using this approach? And what buffer, if anything, would you guys recommend? (Same application, for the use by a 10 year old, to work with some motors, LEDs and what not).
Putting things more generally, what other measures can be taken to protect from newbie mistakes? My first thought was a fuse, but I was told a fuse takes time to burn and is therefore unreliable. How about, putting peripherals on separate circuits, controlled by transistors, so that only transistors connect to the board? That can be done with outputs; what about with inputs?
Ideally, I would like some sort of protection that does not silently swallow circuitry mistakes, but provides feedback (by visibly burning, if it must), for educational value.