Is Yorkville in New York City a good place to live for families with kids?

Yeah, it's pretty good. There are a lot of families in the neighborhood and it's right where all of the prestigious Manhattan private schools are. I, myself, prefer the aesthetic of the Upper West Side to that of the East, but it's definitely a family neighborhood. The only problems are that it's a bit stuffy (people have serious attitudes and entitlement in the UES) and transportation leaves much to be desired.