Personally, I will only hug, hold hands, and kiss my boyfriend (quickly) because I believe anything more than that like long kissing or making out should be kept private and between just us, not out there for everyone to see in a crowded, brightly lit hallway.
It kinda bugs me when people say "it's sooo gross, you go to school to learn not to smooch your boyfriend" because the people who are saying this are obviously either single and bitter, adults who LOVED school as kids, or prude people.
Just cause I don't feel comfortable with it doesn't mean other people should be chastised for wanting to display there love for there boyfriend/girlfriend.

Anyways, whats your opinion on this?