In this experiment, learners float colored ice cubes in hot and cold water. They compare the behavior of the melting ice cubes to understand how temperature is related to ocean currents and how temperature changes water density. The printable eight-page handout includes a series of inquiry-based questions to get learners thinking about how and why water temperature changes along with depth. Illustrated experiment directions and a worksheet help learners use the experiment results to gain a deeper understanding of buoyancy and density.