It was strange to see this question in 2018. Most employers, except probably Mom’s and Pop’s shop do not accept paper job applications. If you think that sending a paper application by mail to the company’s main address will make you look different and stand out, yo are mistaken. Chances are, your resume will go into the bin. All large corporations use Applicant Tracking Systems. T have no capacity to process paper anymore. Smaller companies probably do emails or some sort of cloud applicant tracking. So, to answer your question I would do online application of course. Things might be different for Walmart type of jobs, maybe t can see you in person and accept your job application on paper right in the store. I just would not know, because I never worked those jobs.
Do your application and essay editing on the computer at home or at school. It is easier to make changes on paper before going to school.