Hand-raising in class

Good ol' Hermione...

Do you ever stop to think why, when we're in a classroom, we raise a hand when we want to answer a question (or ask one)? Yes, we're trained from our early childhood in school to do this - when the teacher asks a question and you have an answer, raise your hand, and answer if/when the teacher picks you. It's a way of maintaining a sense of order in a classroom environment: imagine what class would be like if Robin asks a question to the students and suddenly fifty people are shouting out answers.

This practice is pretty much universal, though, and seems to be acceptable everywhere. For example, when you started class at the University, you didn't expect to have to answer professors' questions by throwing a rotten tomato at them, did you? (Okay, that's maybe a bad example.) Raising a hand (and maybe eagerly waving it around) is a practice we learn, something we do to signal whoever's "in charge" that we have something to say.

You can keep a close eye on how people raise their hands to quickly gauge what they might have to say. For instance, if the professor asks a question and instantly someone's hand shoots up (e.g. Hermione Granger), they are probably passionate about the subject and eager to give an answer. On the other hand, if someone only weakly raises a hand and maybe drops it a moment later, they may not be confident in what they wanted to say, or were discouraged in one way or another. (Wanting to ask a question while the professor is in the middle of going over something in class might be an example.)

One thing I've noticed about this practice is how rarely you see people raising their hands in an informal environment (such as while in a group chatting with friends, or sitting around the lunch table). Sure, it happens, but it's not necessarily a widely encouraged practice, nor would it seem imprudent to not raise a hand before talking - except when it interrupts an ongoing conversation... That's just rude.