Lots of good advice in this thread. I’m responding mainly to the OP. It is very good that your son is trying out different extracurriculars, and that he has very good grades. The #1 goal for him should be to keep engaged, with a strong academic program and a variety of EC’s that suit his own interests and talents. Anything he does by 9th grade could be foundational for more advanced studies and EC’s, but it’s likely that he will select and focus on just a few of them.
IMO he should not favor any EC just because he (or his parents) think it’s the one that will get him into an elite college. Nor should he become a serial joiner so he can count up how many clubs he’s in, or how many hours he devotes to some service activity.
It’s hard to predict that someone will be a leader or an “award winner” in an EC. It’s not just a matter of commitment and time. It takes luck and good family and school support. If that doesn’t come, however, the effort and time devoted to EC’s build out a student’s skill-set and may motivate him to learn some new things on his own.
My older child was not very gregarious, had minimal athletic skill, and was easily bored by makework in school. He never was driven to get the highest possible grades. But he got very good grades, had strong aptitude in math and was verbally sophisticated from early school years. In middle school, he placed 2nd in the state in a math competition. But he didn’t want to be a mathematician. However, this showed that he had a facility, a skill that he might apply in other areas.
In 9th grade he kind of fell into policy debate after showing up at a recruiting meeting in high school. By 12th grade he won a state individual championship (his team finished 2nd in the team competition). This was an activity that slaked his competitive spirit, challenged him intellectually, and allowed nerdiness to flourish in all its glory. It had nothing to do with math, but rewarded logical thinking, deep research, practice, and teamwork. It helped him to overcome his loner mentality.
His second major EC in high school was journalism. He started out writing about sports and ended up as opinion editor of the school paper, which allowed him to have a voice on many matters – some within the school, and some within the community. He won a couple of statewide high school journalism awards for opinion writing.
Aside from debate, journalism, and schoolwork, there was his main hobby: fantasy baseball. Like his efforts in policy debate, it promoted a habit of research and information (data) collecting. He taught himself to use spreadsheets so that he could manage his baseball teams. His early interest in baseball statistics (as data) also stimulated his interest in applied statistics more broadly. In high school he was testing statistical models to determine, for example, how much the size of a city’s population accounted for season attendance, after taking into account other factors (stadium size, team win percentage, etc.). (I helped him to learn how to use a canned statistical program for this purpose. But then he was on his own.)
In sum, we had no big plan for him and he had no plan himself to develop EC’s so that he could get into college. I don’t think he belonged to any school clubs aside from the debate team. But he had three foci in his extracurricular life that consumed an enormous share of his time: policy debate (and politics), journalism, and fantasy baseball. These almost define what he’s doing now in his career, more than a dozen years out of college. And he gets paid for it.