I made it in without any "formal work experience", however, lots of volunteer hours, academics, sports, as well as other extracurricular activities consumed most of my time throughout high school
I definitely echo what is said by the reply above^. I would recommend talking about a more personal experience that make you who you are today that someone would't know just from looking at your list of accomplishments/resume. Topics that lie along the lines of developing grit, overcoming...