I will offer this suggestion. It will probably make you stand out from your peers, but not from any normal suit/tie function.
If you go tux, that is basically all out. If your school isn't know for it's "dapperness", you might wish to go with the suit. Hence:
Black tie (go for grenadine if you can)
and then find a mint colored flower for your lapel. Extra points if it is a real flower.
It is subtle, yet obvious that you...