I am not a father, but what I observe works best if the father (or mother) takes the hobby himself first. Kids really seem to be motivated to learn from parents, but you need to let them come to you, instead of you forcing them to learn something you are not interested doing yourself (even in small doses).
I'm a father and you're spot on. It's easy to project what you would like children to get into and just tell them to try it, but it's essential to show that you're into it as well (even -- and especially -- if you're not!)
