A pace stick is a special tool that some important people in military or marching bands use to make sure everyone is walking at the same speed. It looks like two long sticks stuck together in the middle, almost like a giant pair of scissors. When the important person is walking, they hold the pace stick in the middle and swing it back and forth. This helps them count how many steps everyone takes in a certain amount of time, so they can make sure everyone is keeping the same pace. It's kind of like playing a game of follow the leader, but the leader uses the pace stick to help them out!