Classroom manner: is it polite to chat during a lecture in Canada? It's a specific question about academic norms in Canada.

I am not Canadian, but I personally find students chatting while the lecturer is talking is highly impolite, disturbing, and unrespectful to the lecturer. If I am lecturing, it would definitely make me upset if I notice audience is not paying attention to my lecture. I either would take it as my lecture is boring, or something similar.

However, since I am not Canadian, my rule might not apply in this specific cultural background. Would this be considered rude in general in Canada? How's the kids educated here in Canada?

Also, if this is indeed considered rude, how should I, as a part of audience, resolve this nicely and cleanly?

If you think the situations in the States are similar, I would also like to hear about that as well.



Update:

Though I didn't mention, I meant situation in post secondary institutions, mainly universities, and majorly undergraduate lectures.
I think these are just Canadian kids who are just being rude--sometimes younger students will test what they can get away with. I cannot imagine any situation where treating the lecturer like a TV would be acceptable. Tell them you're trying to listen to the lecture and not to them.