Challenge the children to rescue whatever is trapped in the ice!
Early Learning Goal links
- Understanding the World ELG: Past and Present
- Understanding the World ELG: People, Culture and Communities
- Understanding the World ELG: The Natural World
STEM vocabulary to introduce
Freezing, cold, solid, hard, melting, wet, dripping, smooth, shiny, white, crystals, see through, cloudy, faster, slower
What to do
Fill up the container to be frozen with water and put in your objects. If you are using a rubber glove, secure at the wrist using an elastic bag. Place the container in the freezer overnight.
When it is frozen, remove the ice from the container and put it in the middle of the tough spot or tray.
Tell the children that they are going to be glaciolgists. You could use our glaciologist poster. Tell the children that they are going to be curious about the ice, and find a way to rescue the object from the ice without touching it. They will need to be observant and notice what happens when they try didn’t ways to rescue the object. They will need to be resilient as it could take a long time!
Leave pipettes, warm and cold water and salt for the children to use to rescue the objects. Challenge the children to rescue the objects without touching the ice with any part of their body or clothing.
Questions to ask to support and extend learning
You could ask:
- What does the ice look and feel like?
- What can you see inside it?
- How will you rescue the trapped objects?
- Why do you think that will work?
- What else could you try?
- What makes ice melt faster?
- What makes ice melt the fastest?
Other things to try
Remember to refer to the children as glaciologists and praise them for using the attributes. You could say things like:
“You have been curious like a glaciologist to investigate the quickest way to rescue something from the ice.”
“Well done, you observed how quickly the water and the salt melted the ice.”
“You have been resilient like a glaciologist, as you didn’t give u, you kept on trying until you completed the ice rescue!”
The science of melting ice
We have put together some useful information about the science of melting ice to accompany this activity. Don’t worry this is for your information only and to help you answer any questions children may have. We don’t expect you to explain this to the children in your setting!
Why does ice melt?
Ice melts when the movement of the water molecules is enough to break the weak bonds between them. As the ice heats up the molecules start to move faster. At around 0 °C the movement of the molecules can break the bonds and the molecules can move further apart. The ice melts and forms liquid water.
Why does warm water make ice melt faster?
Warmer water contains more heat energy, causing the molecules to move faster and the bonds between molecules to be broken faster to form liquid water.
Why does salt make it melt faster?
Salt lowers the freezing point of water. This is called “freezing point depression.” The salt makes it harder for the water molecules to bond together to form a solid. In water, salt will dissolve into separate sodium ions and chloride ions. More ions mean more ions getting in the way of the ice bonds.
Why does ice melt faster on the surface?
During melting, the water molecules absorb heat energy. This heat is transferred from the water, air or object surrounding or touching the ice and is why an ice cube melts more quickly on the outside and retains its coldness and solidity longer at the centre.
What you’ll need
- Small plastic or rubber items to be rescued (dinosaurs, animals, play people)
- A container big enough for them to float around easily – a rubber glove looks effective
- A freezer
- A tray
- Pipettes (or plastic straws if you don’t have any)
- Beakers of warm water (coloured with food colouring if you wish)
- The glaciologist poster
- 5 minutes to create the item to freeze
- Freezing time
- 10 minutes or so for the activity