Elasticity is the nature of an object to return to its original size and shape after being stretched or compressed. Elastic force is the ability of an object to return to its initial size and shape when the force is removed after being applied to the object. There are many elastic bodies around us. The most common examples include spring and rubber band. These elastic bodies are widely used not only in our daily life but also across the industry. Let‟s make a rubber band gun and shoot the rubber band based on theprinciple of elasticity.