I'm interested as well. And yeah, I'm entering high school as well. I'm felt what you're feeling right now when I was doing scheduling.
But first, you have to start off small and start learning some programming. You have to decided whether you aim for designing the game or coding the game. I'm aiming to be a programmer.
You should learn some computer languages, like HTML, which is used for making websites, and C++, the main video gaming coding language. You could learn HTML on your own, C++ you might need a little help. There's tons of websites on the internet.
Game Programming, An Introduction - GameCareerGuide.com
If not, go into the designing field. Would you like to design the box, characters, etc.? Be familiar with programs like Photoshop, Paint Shop etc. If there's any drawing, graphic design classes, take them.
For clubs, take anything computer or art related. Maybe a Digital Photography club etc.
Don't go off to Japan yet. There's still lots to worry about, like SATs O_O.