Superhero Science Experiment - Buoyancy Experiment for Kids

I set my children a challenge yesterday to make a superhero figure float as a fun superhero science experiment. The activity itself was easy to set up, almost mess free and kept my three busy for at least an hour as they experimented with different ways to make their figures float.

Superhero science experiment - Make a Superhero float - buoyancy experiment for kids — Superhero STEM Challenge

Superhero Science Experiment – what you’ll need

Container to hold water

Figures

Sellotape

Materials to test – we used bubble wrap and chopped up pool noodles, but you could test with anything as long as it floats.

Image of a suoerhero toy figure surrounded by bubble wrap and pool noodle pieces

How to make a superhero float

We talked a little about why some things float and some items sink, then we thought about why children who can’t swim wear arm bands and how we could give our figure the same buoyancy, then I left the children to test and explore themselves.

These were my arm bands for Spiderman.

spiderman wearing pool noodle arm bands for a buoyancy science experiment

Spiderman figure with arm bands - science for kids - superhero experiment

My 9 year old chose to make a raft like structure with the pool noodles, but then after seeing my idea made a hole in the centre of a noodle circle and simply pushed the figure inside like a circular float.

superhero floating on a DIY float for a science activity

My 5 year old used the bubble wrap to fashion large arm bands.

superman wrapped in bubble wrap for a science activity

Why does the superhero float?

Although the bubble wrap or pool noodle makes the figure weigh a little more, it also displaces more water making the figure more buoyant.

The pockets of air in the bubble wrap and pool noodle mean that the figure and bubble wrap together are less dense than the water, making the figure float.