Order objects by mass

Mass describes how heavy or light an object is, independent of its size or appearance. The learner compares the masses of several objects, uses heavier, lighter, and equal in mass, and orders them from lightest to heaviest or vice versa, reasoning that if one object is heavier than a second and the second heavier than a third, the first is heavier than the third. This informal ordering does not include numerical measurement with standard units.