This document contains notes from two science lessons on sound for year 5 students. The first lesson introduces the concepts of sound, vibrations, and sources of sound. It explains that sound is produced by vibration and discusses examples of sound sources. The second lesson covers volume of sound and how loudness depends on the amount of energy in the sound. It identifies louder and softer sounds as examples and explains the importance of ear protection from very loud sounds. The objective of both lessons is for students to understand sound, sources of sound, and volume of sound.