Presentation is everything, yes I know we are not suppose to judge a book by it's cover, but, c'mon something got to give. Look the part, if you want a teaching position, you can not come in looking like your desperate for a job, even if that is the case. If you are applying for an administrative job and the position requires for you to have excel skills. Practice and learn the skills you need before going into an interview. Think about it this way, if you were the employer, would you hire yourself, just by how you dress or the skills you have ?