Recently we have been trying to sort out what sort of ballet classes Elli should take. She is desperately in love with ballerinas since presumably they have a lot in common with princesses dressed in fancy gowns (also they all wear pink, apparently...) and wants to join their august ranks. This all despite the fact that before she was born we were absolutely set on not raising her to conform to gender norms and were planning on dressing her in colours that are not pink and getting her building sets instead of dolls. Turns out popular culture trumps Mom and Dad's plans every time. The things I have seen in ballet schools for small girls have really made me shake my head in dismay.
Some of them seem quite good, like the one she is attending next week. They ask for some kind of gymnastic or dance shoe and a one piece outfit for dancing and exercising in. They plan on having the kids do some yoga, some trips to the park, play some games and then do ballet. This strikes me as a great plan for 4 year olds. They likely will find continuous ballet practice boring and unpleasant and after 3 hours of repeating basic exercises would turn into either weeping piles or berserking terrors. The other extreme is the 'fancy' ballet school which wanted me to spend ~$250 on an outfit for ballet and had rules dictating the one acceptable hairdo - any performer who showed up without the correct hairdo would be sent home. This in a class for 4 year olds! The fancy school also charged what worked out to $35 for each 45 minute lesson which seems to me to be the most ridiculously high cost for entertainment I have ever seen.
I suspect though that if you really desperately want your kid to be a virtuoso you need to get them involved in some brutal class that trains them from a very young age. Most people who end up being prodigies recall spending outrageous amounts of time while very young trying to become the greatest golfer / dancer / cellist / gymnast in the world. It goes back to the idea of needing 10,000 hours of practice to absolutely master a specific skill - the earlier you get started the faster you achieve that peak. Of course it also helps that the kids that practice the hardest at very young ages get accepted to the best schools, find the best teachers and get involved in the hardcore community in whatever their field of endeavour is. That community more than anything else I think is what allows people to develop into wonders at a particular talent.
Of course I put no stock at all in shoving a young child into a skill that they did not choose on their own. Too often this is the result of parents desperately trying to compensate for their own failures or humiliations and has nothing to do whatever with what the kids want. My strategy is to let Elli get really involved in something if she really wants to do it herself. If she decides she wants to train for the Olympics in synchronized otter wrestling or some other such nonsense I will let her go at it but any pressure will be entirely internal. I don't see that frenetic attempts at world domination particularly lead to a good life.