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Units from the metric system can be used to describe the mass, volume or length of an object. Mass is measured in grams (g) and kilograms (kg). Volume is measured in millilitres (ml) and litres (l).

Use a marker, pencils, lollipop sticks, your hand, foot, or anything, as a unit of measurement to measure the height of your family members, rooms in your house, or whatever you fancy measuring. Who ...