I only wish I had known about boarding school when I was in 7th grade. I accidentally stumbled upon Exeter while researching Mark Zuckerberg (weird, I know) in 8th grade, and from there, I only had a few months to get my stuff and my applications together. Needing financial aid is not something substantial (I know others will disagree; this is merely my own opinion), especially if you’re considering big schools like one of the HADES. For example, Exeter and Andover have such large endowment funds that they’ll definitely be able to carry the cost of tuition for you. However, of course, these schools are harder to get into, so you’ll have to keep that in mind.
You have plenty of time! I would suggest for you to join many clubs at school (or start a new one). Being part of a club showcases leadership (and, in some cases, such as MathCounts or other clubs, you can earn awards!). You should also consider starting to do community service. Community service helps round out your character. Last bits of advice: study for the SSAT. A good SSAT score can help you out a bit. And continue to improve your grades at school (if you have a B, focus on raising it to an A. If you have A’s right now, make sure they stay that way.) Good luck!