Swimming is the only thing that's mandatory, because that is a safety thing. Otherwise, we let her pick what she is interested in. My daughter doesn't like team sports, but she does enjoy martial arts, so she takes that. Next year, we'll start guitar lessons--we can't fit a piano in our apartment, and guitar is the kind of instrument you can take with you to college and can enjoy your whole life in many different ways. Reading music is a good skill.

I don't care if she ever does a team sport. When she's older, other sports will become options that she might also enjoy.

I've generally encourage doing one athletic activity + one arts activity. Doing two sports + the arts + expected community service or groups like boy/girl scouts starts to make for a crazy life, esp with multiple kids so you really need to be flexible about what excites your kid and what works with your life/bank account.

For DS, he liked team sports and so did rec level soccer and baseball in ES-MS. He did a theater class in early ES, sang with the school choir and then did trumpet in 4th-7th grade, dropped that and picked up guitar. Now in HS, he doesn't want to do a team sport but runs on his own and still plays guitar. He also learned to golf from my dad + some local lessons and does that occasionally with friends.

DD doesn't like team sports, she did an afterschool "kid fitness" class in early ES and then started fencing in 4th grade. Yes, it can be expensive if you do it at a very competitive level, but she (now in 8th grade) does it at a more casual level for fun/fitness. She practices 3x a week and does probably one tournament per quarter. For arts, she took art classes when little, picked up drums in ES band, switched to french horn in MS and is continuing that into HS.

I think it's also important to be a good example to your kids about these activities. You aren't making them do it to get into college but because it's part of a healthy, happy life. If that's the case, the parents should do the same. Otherwise, IMO, they get the message that these are not important life-long things but just part of the college rat-race. I go to the gym regularly, sing in a church choir, and model community service through our church (which they participate in) and school volunteer work. DH runs and occasionally plays on a work softball team and plays guitar.

Individual sport: Swim. Because it's necessary for safety.
My children have also done dance, gymnastics, and track. But those were there choices after they became competent, safe swimmers.

Team sport: Soccer. It's easy to find life-long leagues at all ability levels. Requires minimal gear.
My children have also done basketball, lacrosse, tennis. Only one continues to play soccer.

Instrument: Piano. Because it's easy to learn to read music with the piano.
My children have also studied guitar, drums, and flute. One still plays piano, another guitar. Guitar is more portable and a great casual pick-up instrument.

My opinions don't change based on sex.

OP, I think you need to wait and see what your kids like and are good at. Fencing is not for everyone. Neither is basketball. Sign them up for things when they're young that they can do once a week and see what they like (and what you like taking them to) and go from there. I think you're setting everyone up for misery if you decide now what your children are going to do for the next 18 years.

Piano, without question. It is the best instrument to start with and just a part of education in my book. Same with swimming. Beyond those two givens, I would expose your kids to any sport they like and see what they have passion for.

If you are looking for something to go into adulthood I’d also consider the arts - sewing, painting, working with glass, ceramics, etc.

I'd pick piano as a musical instrument, running as an individual sport, and ultimate frisbee as a team sport.

I let mine pick. All your suggestions are good choices. We tried a bunch of different sports early on then told kid to pick one. For music, he got to pick one instrument to learn outside school and another one he learns at school (starting in 4th).

DCUM parents like their kids to dabble in a million different things never learning anything. they call it “exposure”.

Why does the choice of activity depend on your child’s gender?

Swimming for individual. Year-round. Builds good overall physique for both boys and girls. Opportunity for high school team, even if you aren't fantastic. Life-guarding is a great summer job in high school and college. As an adult it's low impact and a long term fitness option.

Soccer or basketball for team sport. Cheap equipment, long term easy to just get a couple of friends together to play or join a pickup game. I had my kids do rec soccer in fall and spring and rec basketball in the winter. Kids (& dad) gave up basketball in winter and switched to futsal.

Start piano early (4 or 5 when their hands are big enough). Stick with it as long as they have interest. Being able to read the complex music and perform complex chording and rhythms is wonderful brain development and will lay a musical foundation that if they stop they can still come back as an adult to learn. My kids all stopped in middle school as other activities took priority. No harm in trying an instrument in elementary. My kids enjoyed their various instruments and picked up playing easily with the piano background. Unfortunately, one went to a small high school that had almost no band, and it conflicted with classes, so my oldest dropped playing then. My two younger kids went to a middle school with a terrible band teacher and they stopped playing in middle school. The piano still stick with them though - they will still occasionally play and pick out popular songs for their own entertainment.

Swimming is a mandatory activity because the skill could one day save your child's life.

Fencing is a wonderful individual sport for a child, but realize it requires a lot of travel if you want to do it right (tournament circuit) and is very expensive (you'll want to pay for both private and group lessons, multiple times a week). It's an excellent choice for both your son AND daughter - don't rule it out for girls! And it's easier for you, commute wise, if you are going to a fencing club multiple times a week, to have your children do the sport at the same time. Another bonus - fencing's something your child can enjoy his or her entire life. I see middle aged people fencing at our club every week.

Personally I loved the piano but this is just such a personal thing. My child didn't take to piano despite my insisting on it for a couple years - but now adores the viola. If that's what inspires her and gets her to practice, then that's great. The only thing I would rule out is something like the trumpet or drums because it's just too loud for me to endure.

The only thing I “make” them learn to do is swimming for safety reasons since we spend summers at the local pool and vacation at the beach.

Other than that they do what they want and I try to expose them to different things. The way I get them to try different things is that we will play things a bit around the house at home. If they seem to like doing it, I might say - do you want to try a soccer team? Or even Larlo and Larla are doing basketball, are you interested in trying with them? My kids usually say yes and they each usually do one sport a season.

My kids are 9, 7, and 4 right now. My 9 y/o is not a great athlete just in terms of his body type generally if that makes sense. He has tried soccer, TKD, running club, swimming, basketball, baseball and even archery at summer camp. He’s decent at swimming and baseball and will probably stick with those recreationally for the next few years for fun and probably won’t be “good” enough to do any sport in HS (of course I suppose anything is possible). I will say this kid of mine has a lot of grit so part of the reason he’s decent at swimming is because he wanted to be legal in breast and fly and just didn’t get discouraged and kept working and working at it. I could also see him becoming a baseball youth umpire when he ages out of LL.

Re: music, I’m not sure I’m doing anything right! I offer piano lessons annually bc I think it is a good intro instrument. So far no one has taken me up on the offer and I haven’t forced it! I did tell my oldest last year that it’s important to get a well rounded education, learn new things, and to try different things to see if you like it. So, I said I want you to try some kind of music in ES - I don’t care whether you want to try band, orchestra or chorus but I want you to try something in ES bc it’s a nice opportunity you have to in school to try it. He tried strings in 4th grade and doesn’t like to practice much and I don’t really force it but it seems to have gone well and he’s enjoying it. Basically the entire 4th grade did strings so that helped.

I actually ran track in college and did XC/track and band in HS.
In my experience it’s a pain to try to get kids to go anything they don’t want to do and it’s not worth it IMO.

Lol idk why I started writing a treatise here but now I don’t have time to finish about DCs 2 and 3. Lol.

Well obviously you can't really control that.

My kids are in high school and they have literally tried everything --- things I liked include

chess club, piano, dance, basketball, gymnastics, theater.

Things I didn't love:

soccer (annoying parents), baseball (so long and boring), boy scouts (too much parent involvement and didn't like religious aspect), drums (loud).

But depends on what your kids like, their personality, talent, etc.

If you can pick one individual sport, one team sport & one musical instrument for your boy & girl to learn/take lessons in the long run to adulthood, what are they? I am talking for interest/hobbies, not for competition route.
I have 2 young kids, one preschooler boy & one baby girl. I am suck at all kinds of sports, and does not know how to play any musical instrument, and so do DH. We are both foreigners, and I hear that many parents here help their kids to pick one individual sport, one team sport, and one musical instrument to learn/take lessons for hobbies/fun in the long run which are also good for their physical & mental health/increase confidence/improve interpersonal communication skill something like that.

If I can pick, I want my boy to learn fencing (I hear good for body posture & learn to be patience) or swimming for individual sport, basketball for team sport, and piano or guitar (preferred) or drum for musical instrument
If I can pick, I want my girl to learn dancing (any kind, but preferred ballet) or swimming for individual sport, undecided yet for team sport, and piano (preferred) or guitar for musical instrument

I know parents cannot control kids' interest/hobbies, but parents can try to promote/sell them to the kids.