You’re off to an awesome start! As someone with potential to graduate near the top of your class and be a national merit finalist, you are a likely candidate for big academic scholarships later and for admission to the very top level private universities and to honors programs at public universities. That will all depend on your strategy and success going forward. So here is the game plan that I advise, based on what will be asked for on the college applications and scholarship applications later on.
Courses: Take as many AP courses as possible, as you are doing already starting freshman year, because that will affect your total GPA and ranking in your class among your peers. Winding up in the top 5% of your class can help you get scholarships and admissions to elite honors programs and universities. (I am assuming your school will weight the AP courses for GPA like most schools do.) The key is to make As in the AP courses and also take the corresponding AP exams, and still avoid burnout. If you were to wind up as Valedictorian, there are some scholarships that are only offered to valedictorians, so keep that in mind.
Extracurricular Activities: Colleges will look for leadership roles. If there is not an existing club you are interested in leading one day, then start one and become the instant founder and president. Ideally this should be related to your intended major, so check out the STEM clubs at your school.
Volunteer Work: This should be related to any future career you are considering, and ideally be at one place for a long time (throughout high school, e.g.) – not one day here, and one day there type of volunteering. For example, a future science major can volunteer at a local science or natural history museum staffing educational carts, or volunteer at a hospital.
Competitions/Honors/Awards: Not all honors and awards are the same. They are tiered – international, national, multistate region, state, region within a state, city/county, school. So any awards your school gives you just won’t stack up against other students who have won national and international awards. Keep that in mind as you decide which competitions to look for and enter. STEM competitions include science fairs, tech fairs, hackathons, olympiads, science bowls, mathematical modeling competitions, etc. Most high schools do not advertise all of the opportunities out there, so be sure to search online for options in addition to what you see offered at your school. Try for individual and team-based competitions. Becoming an Eagle Scout as you have planned is very impressive and would qualify as a national honor/award. You will ideally want to have some high level STEM awards as well. Just fyi – membership in “national honor societies” is considered a school level award, not a national award, since each school sets rules for who gets admitted.
Research: Since you are considering STEM-related majors, I strongly suggest getting research experience in a university or government lab while still in high school. These opportunities are out there – some through special programs that take place in the summer, and some that can be all year if you contact a professor and they agree to let you conduct research in their lab. My daughter was offered the chance to conduct research at a top tier university starting age 14. For various reasons she wound up not taking up that offer, but she did later spend a summer working at a government research lab after junior year, and that helped her secure great offers for college admissions and scholarships.
Computing: Every STEM field out there is highly reliant on computers nowadays. Whether you take programming and related classes online (free) or at your school, I recommend getting a strong background in this area before you head off to college. You won’t regret it.
Standardized Tests: You should be taking these every year, to continue getting practice and see where you stand. Prepare seriously each time, and go over what you missed afterward so you keep learning and improving. Because my daughter knew what score to expect when you took the SAT for real, having already taken it every year starting in 7th grade, she knew when her actual SAT score for college came out that it was erroneous. The results said she had made a 610 on verbal, when in fact she had made a 780 – which we found out after challenging the SAT and having them rescore it by hand. Yes, the College Board makes mistakes! That difference in score was the difference in what colleges she got admitted to and what scholarships she was offered.
Startups/Creativity: I just add this because some students really thrive on “starting” things, whether it is a business or a nonprofit or an annual fundraising event. Others thrive on creating things, which could include useful apps or something that could be patented or any number of other things. If you have achievements like these, they of course look great on a college and scholarship application. You don’t need to go out of your way to do this, but it is certainly one more thing that is impressive. For example, there is an MIT/Harvard physics major out there who has been called the “next Einstein” and who is also known as “physics girl.” Her name is Sabrina Gonzalez Pasterski. She impressed colleges because she built her own airplane when very young, and then learned to fly it at a young age. An activity like that would fall in this Startups/Creativity category.