This inertia demonstration kit provides a simple, visual way to demonstrate Newton's First Law of Motion. The apparatus consists of a stand with a receptacle for a ball at the top, an 18mm ball, a square piece of sheet metal, and a trigger made from sheet metal. To demonstrate: place the square sheet on the stand with the ball resting on top, then pull and release the trigger. The sheet slides out from under the ball, and the ball drops into the receptacle by inertia. Suitable for middle school, high school, and introductory college physics instruction.