When I was 15, I was in the exact same boat as you. Here are my recommendations, there are lots of options.
Work on getting good grades, good SAT/ACT scores, and get involved in outside of school activities. The more the better, and positions showing leadership are great for example sports, boy scouts, CAP, music, clubs at school. They want to see someone well rounded.
Start contacting a guard unit in your hometown now, also start talking to congressmen about applying to the Academies. Apply to all of them, also apply for ROTC scholarships in Air Force, Navy, and the Army around the beginning of senior year of high school. My advice is stay away from recruiters because they will try to get you to enlist and tell you how easy it will be to become an officer later and get a pilot slot. Contact the ROTC offices at a University near you to get info on applying.
Make sure you take some high school classes that show some emphasis in math and science, but don't do it to the point it hurts your grades. Once you get into college, your MAJOR DOES NOT MATTER for Air Force pilot slots. If you want to be a test pilot, then you will need an engineering or physics degree, but otherwise, pick a major that you will enjoy and that will allow you to get a decent GPA. Work on GOOD GRADES and being the best cadet you can be. Then, always have a backup plan, because even some of us with perfect vision get medically disqualified for other reasons. Also, you don't need perfect vision, check out
www.wantscheck.com and
www.baseops.net for further information. Goodluck, feel free to PM me.
Lastly, start taking some flying lessons, hours aren't necessary but they definitely help, especially if you are going for a guard slot. They definitely help for ROTC slots in the Air Force, and at the Air Force Academy almost everyone gets a slot right now for those who are qualified and want one (of course this could change in the future).
Myself, just like TONYC, wishes that I had gone the guard route or the reserve route from the beginning had i known back then what I know now.