How to make students perceive "grams", "kilograms" and "tons"

It is best to compare perception with the common material quality in life. For example, "gram" is described by salt used in cooking and pigment squeezed out during painting in art class, while "kilogram" is described by bottled drinks, bottled water, melons and fruits, human body and household appliances, and "ton" is described by cars. I think water is the best way for students to visually compare the sizes of these units, from drip to cup, from cup to bucket, from bucket to bathtub, from bathtub to swimming pool. It is easy for children to master the concept of quality unit.