Just a suggestion to those applying to the Academy. Make sure you apply for a NROTC scholarship as well. Both programs will get you commissioned and will get you to the same place. This way if you don't get into the Academy, you still might qualify for a ROTC scholarship at a civilian school. Basically, have a back up plan and don't rule any of your options out, especially since you are starting to think far ahead now.
As a side note, I wanted to go the Academy, got two nominations and was accepted. I had a small medical problem that kept me out, but that problem wasn't an issue for NROTC. I ended up going to Purdue University on a ROTC scholarship and graduating from there. Just remember, there are plenty of paths to a commission so examine them all to find the best fit for you.