​Are there any organizations who can help me organize a hackathon?

I’m the president of my highschool’s software development community. At the start of the school year, i searched online for hackathons which we could join, i found many for college students, but none for highschoolers, i called many of them to ask if we could still join, but they said we weren’t allowed to. So I thought, why don’t I organize a hackathon in my city for highschoolers to join? Do you know of any organizations/associations/establishments who could be of help to me? For you information, I’m from İzmir, Turkey 🇹🇷, but I would appreciate getting in contact with anybody regardless of where they are from. Thanks!