Brachistochrone curve

Is the straight line always the shortest way? Back in 2013 I visited the "Museo Galileo" in Florence, Italy. I was amazed on what I saw there and specially one object caught my attention. This wooden object made me think about the question asked at the begining of this lines... When I saw this new version of the Maker Ed Challenge my mind went back to that object called The Brachistochrone. Students can work different aspects of this item starting with a bit of History, following with some