I'd say being on either end of the spectrum will be the two ways to get noticed. You can either dressed to rules exactly, or to do something ridiculous like a zoot suit. These stand out because the majority of HS prom are notch lapel, matching long tie and vest, poorly fitted gary's tux shop monstrosities (aw I fell for that my first prom). A great tux will stick out in the minds of others and they won't be able to put their finger on it. I honestly don't even remember if i had a notch or peak lapel the next time around, but just the bow tie made people go "nice." Or you can take the predictable approach and wear a costume. How bout a velvet purple pimp suit?
. A zoot suit (with a cane!) would garner many votes. This is what I think would shock and awe as well as being somewhat proper: a morning(?) jacket with TAILS. Ok so the prom probably isnt being held during the day... but TAILS man. Tails will win it!