For two decades, students walked past an unassuming beige rock on their way to and from class—and occasionally stuck wads of used chewing gum on it. Now, paleontologists have discovered the slab is covered in 200-million-year-old dinosaur tracks,

A slab of rock at an Australian high school, a boulder in a parking lot, and a bookend in a private collection feature 200-million-year-old dinosaur footprints.

Learn more about the schoolyard dinosaur discovery, which found 200-million-year-old fossilized footprints on a boulder from Australia's Early Jurassic period hiding in plain sight.