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.