Check out this blog column (Greg Mankiw is an economist and textbook writer--the book we are currently using) via Taggert at A Random Walk. It references a paper that attempts to explain the increase in attentiveness among parents.
The punch line?
Competition for college admissions.
Read that, instead of the old craw "this will stay on your PERMANENT record" parents are now using the verbal stick "you won't get into any decent college with THOSE [fill in the bad habit du jour] skills!"