Handgrenadeheart pretty much covered all the suggestions I would give, but I'm just going to touch base on everything anyway.
Looking for groups outside of school is a really great idea. Some areas have community groups, so you might have to look around. They aren't always the easiest to find unfortunately. But there may very well be one near you.
Pride events are also wonderful, but they obviously wouldn't happen as often as a group might meet. That said, they're something.
And yes, of course, online is always an option. Of course, not very personal, but you could talk to other people. I like TeenHelp, personally, because the people here are so friendly and helpful. But there are other places aimed specifically at the
LGBT community, like EmptyClosets.