A Frosty Beard for Santa STEM Challenge

Last year, we made an icy snowman using ice, salt and water. This year, it’s Santa’s turn. Draw a Santa face on the outside of a tin can, add ice, salt and water and watch as a frosty beard appears.

You can use the same salt and water science to cool a drink quickly and make ice cream in a bag!

Frost on a can decorated like Santa - a fun activity for learning about the supercooling power of salt

Frosty Beard for Santa

You’ll need

A clean, empty tin can

Coloured pens to decorate

Ice

Salt

Water

How to make a frosty Santa

Decorate the can to look like Santa. We used a mixture of sharpies and chalk pens.

Fill the can with small pieces of ice.

Add a little water

Pour in about three tablespoons of salt

Watch as the frost forms

If it doesn’t work, keep adding ice and salt. The frost should form within 10 minutes and be solid enough to touch the outside of the can.

Frost on the outside of a can decorated like Santa for a science experiment

Why does frost form on the outside of the can?

The icy water temperature is about 0°C, but for frost to form, the icy mixture needs to be much colder, which is why we add salt.

Salt lowers the freezing point of ice, which means at 0°C, the ice starts to melt as its freezing point is lower than zero. To do this, the ice draws heat from the surroundings ( the surface of the tin can ), causing water vapour in the air to condense and freeze on the outside of the can.

Frosty Beard for Santa STEM Challenge

More Festive Science for Kids

If you enjoyed this activity, you’ll love my ULTIMATE list of Christmas Science Experiments, which contains Santa STEM challenges, a FREE pack of paper science experiments, reindeer lava lamps, and lots more!

Don’t forget to download my FREE pack of elf activities, too!