The Pendulum is an interactive puzzle kit to help learn and better understanding the common element in mechanical clocks. The pendulum is one of the basic and most reliable time measuring mechanisms. Its working principle is based on the model’s constant amplitude oscillation under the force of gravity (weight) and potential energy (tension force) of the rubber band. The rubber band powers the mechanism of the model and compensates for the pendulum’s oscillations’ kinetic energy loss.  The model has an anchor escapement controlling the frequency of oscillations, a weight, a scape-wheel, gearing, rubber band, ratchet, and pawl reducing operation error. The model has several means to control the frequency of oscillations: the weight of the pendulum bob, the vertical position of the weight on the pendulum, and the tension of the rubber band.