How do these private schools do the academics, music & sports to such a high standard? Do they also have a very good base if the kids are having sport & music reinforced outside school through their families lifestyles?
It's not so much that they go to a private school, but an obvious factor is money , time spent on practice, as well as discipline and normalising the family lifestyle that lends itself to being good at music and sports, as you have already mentioned.
Having said that our dcs are both state educated; ds plays for a local football club who finished 2nd in the county at the end of this season. He stopped piano at grade 5 though, as it just wasn't his thing but he was disciplined with practice at the time.
Dd on the other hand does so many extra curricular activities as it is. Scouts, 2 types of dance classes, piano, viola. Again, none of these things are cheap.
She is good at lots of things but she cannot be good at everything because of how think spread her time is between them. By the time she comes back from another scout's camp or hike, she barely has time for practice in either instruments. She narrowly missed a merit recently in her grade 6 piano, but her dance grade suffered and she only just passed having missed several lessons because of clashes with other things.