Sink or float

Setting up a sink or float station is an easy way to introduce science to toddlers and preschoolers, inviting them to learn about the concepts of buoyancy and density. This play-based activity combines a very simple science experiment and water-play for fun and engaging learning with your little ones!

What you need:

• A bucket or tub

• Water

• Natural items such as stones, pebbles, leaves, sticks, gum nuts, shells, bark, feathers, etc.

You may like to take a special nature walk to collect as many different items as you can, or use whatever you can find in your own yard.

Now one by one, place the items into the tub and watch… do they float or sink? Before you place each item into the water, ask your child what they think will happen. Through this activity your child will begin to learn that buoyant objects such as leaves will float and more dense objects like rocks will sink.

Depending on how you and your child like to play and learn, you can discuss the science and “why” behind this activity in depth, or simply enjoy observing. There’s no right or wrong way to explore nature and science!

One way to expand this activity is to drop the items from a bit of a height. Some items will make a big SPLASH as they hit the bottom, while others sink down slowly before bobbing back up to the surface. But the same items will always sink and float, regardless of how they enter the water! Hours of fun and learning to be had observing the way each item interacts with the water.

Another way to extend the learning or create a challenge for your child, is to offer them a small pair of tongs to pick up each item. Using tongs is a great way to strengthen find motor skills and coordination, though it does take some practice!