In Year 4 the children have been learning about changing states and the processes that cause it.
Did you know that adding salt to ice lowers the temperature at which it freezes? As the two substances mix, the water draws heat from the surroundings to dissolve the salt, causing a drop in temperature.
We tested this out by making our own liquid ice cream and surrounding it with salt and ice. When the salt causes a drop in temperature, the mixture cools more quickly and the temperature becomes low enough to freeze, leaving us with yummy ice cream! We can still make ice cream when it's snowing, can't we?