Description: Henry Cavendish was the first scientist to measure the gravitational force between two objects in the laboratory using a gravitational torsion balance. In this video physics teacher Andrew Bennett attempts to recreate this experiment. Reading the comments section is very interesting. Pseudoscientific flat-earthers attempt to point out errors in the Mr. Bennett's experiment. Students could attempt to recreate the experiment or join in the conversation.
Description: The Gravity Light converts potential energy that is stored in a weight into light. The principles involved in this design are very similar to the principles in a cuckoo clock, with the potential energy of the weight being converted to solar energy rather than kinetic energy. Gravity Lights can replace kerosene lights in the developing world with a safe alternative. The phenomenon can be used to illustrate the conversion of potential gravitational energy into other forms of energy. More importantly it conveys the message of sustainability and social responsibility.
Description: The Schiehallion experiment was an attempt to measure the mass of the earth using a pendulum and a mountain (Mount Schiehallion). The mass of the mountain was approximated and the deflection of a pendulum due to the gravitational force of the mountain was measured. Students could attempt to do the calculations or even repeat the experiment on a nearby mountain.
Web Resource: Schiehallion Experiment - Wikipedia
Description: In 2012 Felix Baumgartner set the World Record for skydiving from a height of 24 miles. The freefall lasted over four minutes and Felix broke the speed of sound. This phenomenon can be used to introduce the gravitational force being directed down in elementary school. This definition can be expanded upon through middle school and high school to include gravitational fields and application of Newton's Second Law of Motion.
Web Resource: Red Bull Stratos - Wikipedia