Hello, I am also a freshman in high school who wants to be a pilot.  To answer your ADHD question, I believe that if you have ADHD and you can prove that you can pass academically without medication for 12 months, you can still enter a service academy.  I got this information from a source about the United States Air Force Academy.  You should write to a service academy about the exact details for this. 

Remeber that you can still probably be a fighter pilot even though you might have ADHD.  By the way, if you have electives, you might want to take engineering or computer science instead of, say, the arts.  I think that it might increase your chances of being accepted to a service academy if they see that you are intersted in technology.  Also, remember to take at least to years of foreign language.  Four are better.

So, anyways, get good grades, be the best athlete you can be, and good luck with your goal!