I’m a professional musician and I’m going to rock the boat here. I’d say the idea to play, as well as the instrument itself if they want to play, should come from the kid. To get good at this, it takes so much work, that someone would be absolutely miserable if it were somebody else’s dream rather than their own. Kids already have so little control in their lives. I saw this in too many classmates. There are plenty of other things worth doing if this activity isn’t somebody’s thing or isn’t for them right at this moment.