This document discusses three important aspects of using one's voice effectively as a teacher: audibility, variety, and conservation. It emphasizes that teachers must project their voice so students in the back of the class can hear as well as those in the front. Teachers should vary the volume, pace, pitch and tone of their voice to engage students and draw their attention. Proper breathing techniques are important to avoid straining the voice. Teachers must conserve their vocal energy by avoiding shouting and varying their vocal delivery throughout the day.