France, Netherlands, Denmark, former commie block come to mind. It was one of the things that really stuck out to me: how mature/well behaved and independent/confident the children were there (for the most part). There's even books on the topic (Raising Bebe, The Danish Secret to Happy Kids) which I was not aware of until after spending a lot of time in those places. At lot of it has to due with the built environment - kids can literally walk out the front door to parks and stuff unlike in suburban places, but also culture.