by choosing a personal referent for one gram, and explaining your choice. Example: A dime weighs about 1 gram.
by choosing a personal referent for one kilogram, and explaining your choice.
by matching a given standard unit like grams and kilograms to given referents.
by explaining the relationship between 1000 g and 1 kg, using a model.
by estimating the mass of a given object, using personal referents.
by finding and recording the mass of a given 3-D object.
by measuring, using a scale, and recording, using the units g and kg, the mass of given everyday objects.
by providing examples of 3-D objects that have a mass of about 1 g, 100 g and 1 kg.
by finding the mass of two given similar objects with different masses, and explaining the results.
by finding the mass of an object, changing its shape, re-measuring its mass, and explaining the results.