How many AP classes/sports/clubs should I join in junior year?

My dream college is UCLA, but I am also interested in UCB and USC. I’m a freshman taking 6 classes (all honors except for pe and engineering design) and next year, I plan on continuing my honors classes and adding AP Euro. I’m also on the water polo and swim team, and next year, I will be the president of my own club, as well as an executive officer for two more clubs. Lastly, I’ve been playing piano ever since I was 6 and only play competitively now (so it does not require as much time). I’m trying to figure out how many AP’s to take junior year, as well as if I should quit one sport that year and then rejoin senior year.

come back when you are almost done with your sophomore year and ask again.
but in general, elite colleges like to see 4-7 AP’s TOTAL.
my advise , and this is subject to what your grades are by the end of next year, AND how many AP’s are offered by your HS AND what AP classes are offered that interest YOU, is to take 2-3 Jr year and 3 Sr year.

second bit of advise- it will do you NO good to have any “dream” colleges where , regardless of your grades, EC’s, talents, the chances of YOU being rejected are 80-90%.
there are hundreds of great colleges in the US where you can get a great education and where you can be happy
IF you happen to get into one of the colleges that accept a small % of applicants, then rejoice in your good luck.
But don’t waste time “dreaming” about any college that rejects the vast majority of qualified students, because there is not enough room.

It is not the most APs, wins. You need to figure out which makes sense to you and which you can do well in.

Stanford:
We expect applicants to pursue a reasonably challenging curriculum, choosing courses from among the most demanding courses available at your school. We ask you to exercise good judgment and to consult with your counselor, teachers and parents as you construct a curriculum that is right for you. Our hope is that your curriculum will inspire you to develop your intellectual passions, not suffer from unnecessary stress. The students who thrive at Stanford are those who are genuinely excited about learning, **not necessarily those who take every single AP or IB, Honors or Accelerated class just because it has that designation.[\b]

In addition to what every one else says, I’d add:

If you’re two busy to do two sports your junior year, then you’ll likely to be too busy to do 2 your senior year. If you want to drop a sport, that’s fine. But expecting to rejoin is also not fair to your teammates, particularly in a cut sport.