A variety of activities look good on the transcript!
I took a very different route than my siblings. I took ballet 6 days/week well into high school. I also played three instruments, was part of my music school's tuition-free conservatory, and was part of the Composer's Forum (we did a lot of composing music and got our pieces played by professional musicians). I also did a lot of volunteering: altar server and lector at my church for nine years, playing music at the retirement center, preparing food/cleaning up at a soup kitchen (REALLY interesting experience; I highly recommend this; since I live on the south side of Chicago, I got to meet a lot of interesting folks), preparing bags/organizing canned goods/checking people in at a food pantry, helping with fundraising at Chicago classical music radio station, etc. I also had a job at a research library.
My siblings took the sports route. They are all national fencers, and schools both officially and unofficially recruit for the sport if you are nationally-ranked. Obviously not feasible for everyone to do this, though, because, even with scholarships, a lot depends on your location and which coaches are in the area--as well as how much one can travel for competitions. In addition to this, my siblings did/are doing a variety of other things: volunteering at the aquarium, volunteering at a children's hospital for kids with chronic illnesses/disabilities/dealing with neglect/etc., tutoring a variety of subjects (math, writing, Latin, Greek, fencing), babysitting, getting certified with CPR and some other things (clearly I was in college when that happened, so I didn't know what was going on at home!), playing instruments (cello, flute) and singing, participating in the same music program I did, participating with permission in a UChicago choir, participating in the Chicago Youth Symphony Orchestras (top level and level under that one), etc.
So, as you can see, we did a variety of things. I know that there were a lot of factors besides extracurriculars that were important, though. Two of my siblings are at Princeton. (The third is applying to colleges now.) I went to the University of Chicago. Something worked!