When people spit out globs of chewing gum, the gooey stuff tends to stick around. That’s because the main ingredient in most gum is a rubber-like material that doesn’t biodegrade, or break down naturally. To keep used gum off sidewalks, French design students Hugo Maupetit and Vivian Fischer created a method to recycle it—into skateboard wheels!
“Pollution from chewing gum is a problem, particularly in cities,” says Maupetit. He and Fischer installed collection boards in Nantes, France, where people could stick their discarded gum. The pair collected the chewed wads, which could then be cleaned, melted, and molded into colorful wheels for skateboards.