An introduction to the freezing and melting of water. On the lower slopes of a mountain, snow and ice melt and form a stream. Snow can be easily picked up as it is crunchy and hard. In contrast, water is hard to pick up with your hands.

First broadcast:
9 October 2007

Useful as an introduction to changes of states. The children could investigate what temperatures are required for a change of state using water, chocolate, caramel and so on. They could use their findings to investigate if the snowman will melt faster or slower when wearing clothes compared to a snowman not wearing clothes. This could then lead on to thermal insulators and conductors.