An essential part of projectile studies is the monkey and hunter problem. A monkey sees a hunter take aim. If he lets go when the hunter fires will he drop so that the bullet passes harmlessly overhead or should he sit still and watch the bullet pass harmlessly underneath since it is pulled down by the gravitational field? This apparatus allows for an interactive study of the problem by students. A spring powered "gun" fires ping pong ball "bullets" at a model monkey supported from a small electromagnet. The electromagnet is switched off at the instant the projectile leaves the gun. The system has everything required except a low voltage power supply and laboratory stand for the electromagnet.