You may have noticed a paradigm shift lately in the thinking about what kids need to succeed in life.
The old paradigm was all about reasoning and acquired knowledge. The new paradigm, which burst into the mainstream with Paul Tough's hugely successful 2013 book, "How Children Succeed," is all about character skills such as perseverance, curiosity and - everyone's new favorite word - grit.
Tough's book had an impact in part because it was highly readable and compelling. By contrast, a new research paper published today by the National Bureau of Economic Research is daunting, long and full of jargon.
But this paper could still be very useful.