To create my pendulum I used a piece of string and a fishing bobber I found in my basement. However, you can use almost any object hanging from a line. Even your shoe! Hold onto your shoe laces and let your shoe hang from the end. What you notice about how your pendulum swings as you raise it to different heights? How is that related to the pendulum's potential and kinetic energy? How high can you raise your pendulum and it still swing back and forth? Can you raise your pendulum too high, what happens eventually? Go on, discover it for yourself!