Hey Michael, sounds like overall your interested in developing capitol and education, until your 18 and can hit the market running, if not sooner. Thats a solid plan. You have a lot of options. My advice: Your end goal is to be an entrepreneur, so start working jobs that are not only going to help you build capitol for down the line but also teach you the skills for your future ambitions. So as many have mentioned above, and I'm sure you're tired of hearing it, start a grass mowing business, or something of the like. It can be anything really but in this example you gain experience:
building something from nothing
dealing with rejection - people are gonna say no
experience with success - people are gonna say yes, and you get the experience of analyzing why and how to improve your approach
Hard work - there is never a substitute for this
You would learn more than that but those are some, additionally, if you wanted to treat it like a real business, then you aggressively work on growing and learn even more, build it into a business:
Expand your clientele until you need to hire additional workers to keep up with demand
You will now have to manage others and engage with different personalities in order to make it work
Add additional marketing to grow and on and on
So from the above, you can probably see a massive investment of your time and determination with the pay out of capitol and experience which will directly relate to your end goals as a real estate investor. It's the business skills and experience that you would really be profiting from and if done correctly you would build capitol at the same time.
Just some thoughts, regardless of what you do, I recommend finding/making a job that teaches you solid skills to aid you in the future. Oh and don't discount the military or school, it would be a long way out but as someone who has done both the knowledge you can gain from both through experience is the real gain. It's the intangible knowledge.