For those of you who haven’t seen the original Caine’s Arcade movie, I highly recommend you see it. It started a worldwide phenomenon of visitors to the 9 year-old cardboard arcade in his father’s hardware store, but it also spawned an incredible array of new cardboard inventions by kids around the world. As a result, on the 1-year anniversary of the flash mob that formed at Caine’s Arcade, Nirvan Mullick (the filmmaker who originally made the Caine’s Arcade video and who started the Imagination Foundation) has now launched the Cardboard Challenge, in which kids are encouraged to create objects, games, and structures (anything you want!) out of cardboard. The foundation calls it a Global Day of Play. It’s today (Oct. 6), but I encourage you to embrace this feeling every day. I remember many years as a child building forts and hurdles out of packing crates, making pots with modeling clay, and during one semester living abroad, making up no fewer than 10 games involving a single tennis ball and a dead tree in the back yard of the house we were renting. There is good research suggesting that fostering imagination keeps kids interested and engaged in learning science and math, and this is an awesome way to do it.