Build This DIY Slingshot Smash Challenge Using Stuff You Already Have If you've ever wanted to turn your backyard into a real-life version of Angry Birds, this might be the most fun project you'll build all year. This DIY Slingshot Smash game combines giant cardboard towers, a homemade slingshot, and soft balls to create an activity that gets kids laughing, moving, competing, and burning off endless amounts of energy. It's simple, inexpensive, and ridiculously entertaining. B