A WHOLE NEW PLAYGROUND: There's a lot of talk about "digital literacy" education as one of the "21st century skills" that our kids need. Forbes recently looked at how The School at Columbia University (serving K-8) implements such a program. Along with hosting discussions on how to behave online, administrators monitor an in-house social network built just for students. Sparks do fly when sixth graders take playground fights and popularity contests online. But the site gets wiped at the end of the year and students can start with a clean slate. Says Karen Blumberg, the school's technology integrator, "if you're going to make a mistake, make it here, before it's public and permanent."