I've been going to an arts school since 6th grade. I have eight 80 minute classes per semester, four classes per day split into an A/B schedule. I take all four core classes and the rest are filled by classes for my "pathway" (my school's name for your art focus). I have two, creative writing and visual arts.
I'm told that this is the kind of stuff that usually gets classified as extracurriculars, but by definition, my art classes aren't. They're in my curriculum, and because I have four art classes and four core classes they're just as large a part of my experience as my core classes. Additionally, there's a lot of crossover between English and Creative Writing because creative writers can count certain English classes as part of their pathway.
Most of my free time I don't spend doing video games or whatnot is spent on art, whether it's for school or not. I've taken some art classes outside of school on and off since about sophomore year, and my school requires volunteer hours to graduate (I've been forced to save them for senior year due to COVID), so I think those would count, but other than that I don't have any.
What could improve my extracurriculars? Do I even need to have more, given my unique situation?
The answer might depend a bit on where you are considering going to school. Are you planning for an art school or going to study something else? If you're planning on going to an art school you might be OK as-is, but it definitely wouldn't hurt to add more things. If you're planning on studying something besides art and don't plan on attending an art school then I would strongly recommend you add more ECs.
Maybe check out this list: https://blog.collegevine.com/extracurriculars-for-high-schoolers-interested-in-visual-arts/ and see if any of those ECs interest you. And remember, not everything you do has to be in art. It's perfectly OK to pursue other things that interest you because your passion and interest for art will be apparent in your application already.
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