If you know what area you would like to major in, I would make an appointment to talk with someone in that department. It could be a better way to spend your time than chatting up admissions folks, who see thousands of kids a year and will not remember you in three years time, unless you make a pest of yourself, in which case the impressions will be negative. Talking with the department faculty or with students in that department could yield some good material for the “why Harvard?” essay you will have to write eventually.