Freezing Lakes

In some parts of the world, lakes freeze during winter. In this activity learners will explore water’s unique properties of freezing and melting, and how these relate to density and temperature. Learners will use food coloring to investigate how hot, cold, and frozen water mix in this model. Step-by-step instructions are included with photos and safety recommendations. Activity guide includes a “What’s going on?” explanation and relevant connections to the density of water and how organisms survive in a frozen lake.

Materials List:

• Loaf pan-sized container, glass or clear plastic


• Blue and red food coloring


• Hot and cold water


• Two drinking cups of equal size (approximately 250 – 500 mL (1-2 c)) that can hold hot and cold water


• 12 blue ice cubes (made in advance using blue food coloring)


• Container for holding and pouring water (such as a pitcher)


• Spoon