And I didn't do anything like "teaching them perl". In fact, I think I may have actually used bash; and if I were doing it today I'd probably use python. The

And I didn't do anything like "teaching them perl". In fact, I think I may have actually used bash; and if I were doing it today I'd probably use python. The point was to have something that you could reasonably guess what it was doing from looking at it. You don't have to know anything about perl replace "A" with "E" and vice versa. And although I wouldn't call this exercise "fun", it's something that connects with a part of their life they understand. Nobody would actually write a script like this, but someone could totally write a function like this as part of a larger program, and have exactly the kind of "bug" that was displayed there; or, could be hacked in exactly the same way. Kids are sharp enough to know when a skill is going to be useful, even if it's not "fun".