Which Cup Has More?

This month we are exploring the concept of the conservation of liquids, which is the principle that a certain volume of water will remain the same no matter what shape container it is placed in. For example, a pint of water will be the same amount in a short, wide container as it will be in a tall, narrow container, despite how it might look different in the two containers. Water play is a great opportunity for your child to experiment with the conservation of liquids. Your child will love this fun, hands-on experience!

Age-appropriate Adaptations:

  • Two-year-olds—Your child can explore the volume of liquids during bathtime or playtime. Give your child several containers of various shapes and sizes to freely play with in the bath or sink. Your child can also pretend to give plastic baby dolls a bath or he can have a ‘carwash’ to clean his toy cars. Show your child how the water level changes when objects are placed in or taken out of the tub or sink.
  • Three-year-olds—Create a dishwashing station sensory bin by adding water, soap, sponges, brushes, loofahs, washcloths, and various dishes (bowls, cups, scoops, plates, utensils, dish strainers, measuring cups, etc.) to a large plastic tub or sink. Encourage your child to pretend to wash the dishes. Ask your child to pour the water from one container to another to see how that amount looks different in each container. This would be a great outdoor activity, but it can also be done inside with a towel or blanket placed underneath the tub.
  • Four-/Five-year-olds—Conduct a simple experiment to explore water conservation. Use food coloring to pour different amounts of colored water into various sized containers. The food coloring will help your child to more easily see the volume of the liquids. See if your child can pour water to try to make the same amount of water in matching-sized containers. She can check to see if the amounts match using measuring cups. Talk about conservation by showing how 2 cups of water in the tall narrow container is the same as 2 cups of water in the short wide container even though the water levels may look different.

Skills Supported: conservation of liquids, fine motor skills (pouring), imagination, scientific experimentation