It's great that you are thinking ahead! Education certainly comes with a hefty price. That said, there are a number of ways to finance education, including scholarships and loans. So at this very early stage in your schooling, I'd suggest that making money should not be your sole focus.
Instead, I'd suggest pursuing experiences that resonate with you most. You will get much more out of any experience, volunteer or paid, if you are deeply engaged. A position to which you are genuinely committed can open up new previously unconsidered opportunities and better define your interests. Furthermore, it can help you build a well-rounded perspective on issues of interest to you, ultimately making you a more compelling applicant to colleges.
In short: focus on cultivating your interests for now!