IT'S ELEMENTAL, MY DEAR: Edtech'ers find the best holiday gifts. Here's one of our fav's: the key for unlocking the secrets of all the world's elements. Read the book. Get the app. Use the placemat? (And nope, this message was neither paid for nor endorsed by anybody other than Betsy's kids.) What's on your list? Do let us know. We've still got shopping to do. And don't forget to put something in the stocking of your local teacher!