We call the unit of measurement for work a Newton-Meter. Gravity is the force of one object pulling on another object. Isaac Newton began to take interest in gravity when he saw an apple fall from a tree. He concluded that the force that causes apples to fall must also be the pull on all bodies in the earth's sphere toward the earth's center. Newton also studied force.
Force is anything that causes a change in motion.
Newton realized that the force applied must be greater than the resistance of an object to cause movement. To measure the distance caused by a force we use meters. Ask ALL children to describe the direction in which it falls. Work is done when a force moves something. Gravity is a force which acts upon objects and systems.