parkereloise, I think it's lucky that you live in the city. I am personally envious.
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If fashion is what you really want, I would definitely stay in NY for college. I would love to go to college there but it's so expensive and I get tuition for practically free in my state of residence which is why I'm not looking to transfer. You will probably be able to find good rates at a public university since you'll have residency for NY state.
When you are finally in college, you can arrange your class schedule to allow weekday time for internships. And you can apply for the fall/winter/spring positions which I think is a huge advantage. I don't know for a fact, but I assume they are less competitive to get than summer ones since less people live in the city year-round and people from all over the country (like me) apply for the summer positions. Plus, living there you will be in town for fashion weeks no matter what. I think this is a tremendous advantage because the academic calendar doesn't allow this for me. I have to always be back in my own state at school. So even if I get a summer internship that has an opportunity to work during fashion week, I can't because I always have to go back home to school at the end of August.
So I would say, count your blessings, you definitely have a few IMO.
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And yeah, see what else you can do in the meantime per
BetteT's suggestions.
BTW, I saw some kind of pseudo-internship (more like "volunteers needed") listing and it was basically just asking for people to hand out magazines (I think it was W or something and I think it was paid!) for a few hours outside the tents at fashion week. I doubt they would care if someone still in high school did a task like that and you'd get to be in the middle of, or at least right outside of the action. I'm sorry but I just looked through a bunch of links and I can't find that listing again right now. Maybe it's in a thread here . . . but anyway, my point is during fashion weeks there is a lot of demand for random jobs and help. Good luck either way! And if you don't get great opportunities in high school, don't worry. Just do good in school and get what you can later.