the smartest kids in my class usually understand concepts and make connections before i do
almost all of them (except 1) are pretty laid back
they are nice and don't act arrogantly -which is also nice
they also come up with new ideas during class -things that would take me an hour to come up with
..this all depends on the op's definition of 'smart'. i think the 'smartest' kids in my class are the ones that are innately intelligent without trying too hard -I can't help but feel a bit of jealousy sometimes.