Things you need
- Grocery bag after a shop.
After you and your child get home from a trip to the supermarket, have them test the mass of the bags to determine which is the lightest by holding one in each hand. Comparing the weight of objects in this way is called 'hefting'.
Let your child choose the bags they would like to test.
Ask your child to hold one bag in each hand and lift them up to feel which one is heavier or lighter.
Repeat this with all of the bags, and order them from the lightest to the heaviest.