I swear someone else asked this exact question a while back -- coming to the St Louis area because of Logan, and what's the immediate area like. I wonder if you could search for the archives and figure out who that was.
The grade schools around that area are pretty good -- it's in the Parkway school district.
One of my kids was in Scouts with the daughter of one of the professors. I remember going over to their condo, which was reasonably near Logan over in Ballwin. TONS of kids in the neighborhood, and a nice little park nearby. The area around there is more suburban, though -- you'd have a Whole Foods and Trader Joes and Cotton Babies and all that nearby, but you'd tend to drive to them, although there are some bike lanes and I think they're trying to encourage more bikes. If you want to walk to lots of things you'll need to live closer to the city. Public transport is pretty dismal.
St. Louis is, overall, a very family-oriented area. It's a giant small town. Really. In South County everyone has known each other forever, and will start conversations by asking which high school you went to. West County (where Logan is) has more of a mix of people from all over.