Water Xylophone

Different water levels produce different pitches. Ask students to predict what will happen. Tap each cup gently. Key idea: Water changes the effective mass/vibration frequency of the cup system. Ask: Which cup will sound highest? Safety and cleanup: Use plastic cups if possible; tap gently. https://www.pbs.org/parents/crafts-and-experiments/discover-pitch-with-a-water-xylophone