Are you done?

[Delapoma]

Which one is better? .Are you done? or Did you finish?....in a school when the teacher wants to know if their students have finished the exercise.Thanks.

[IvanV]

To me, 'Are you done?' implies a certain degree of impatience. You may go better with 'Have you finished?'. :)

Though it's the tone that says the most, so I think you shouldn't be worried too much. :)

[bhaisahab]

Definitely 'Have you finished?'

[Daruma]

What about "Are you finished"?

<finished> [adjective]
no longer doing sth or dealing with somebody / something
- I won’t be finished for another hour.
- I’m not finished with you yet.

[maral55]

Can we say "I am finished"? or do we have to say "I'm done." I mean for "I" specifically.

[Daruma]

finished - Definition from Longman English Dictionary Online
<finished>
[not before noun] no longer doing, dealing with, or using something [= done]:
I'm almost finished.

[Anglika]

Can we say "I am finished"? or do we have to say "I'm done." I mean for "I" specifically.

You can say either. "I am finished" is preferable