A folding pocketknife is extremely unlikely to be considered a weapon, so I wouldn't worry (I carry a folder in my pocket at my school, too, and none of the campus police have cared). Carrying a gun in the parking lot is an interesting mix, however. According to my school's weapons prohibition, the parking lot is "on campus," and in Oklahoma it is illegal to carry a concealed (and presumably open) firearm "on campus," however, Oklahoma law creates an specific exemption for the parking lot. So, at my school, I could be expelled for keeping a pistol in the glove box, but if I have a CCW, I could not be prosecuted. As it's a private university, and therefore private property, I don't push it there.