As far as I can see, there really aren’t that many gap-year opportunities in the US as far as internships, volunteer work, etc. that you don’t have to pay for. Many programs want you to be a student. I worked at McDonald’s in high school, but they never let me work more than a few hours a week. I don’t know if it’s because I wasn’t 18 or because I was a crummy employee due to my lack of experience, but I figured if I took a gap year to work I would just end up with a job like that.