Make your expectations for voice level clear with a visual voice level chart!
Use this voice level arrow with a Voice Level Expectations Chart (see my voice level expectations listings) to indicate your expected voice level. I print my voice level chart as large as possible (minimum size 11" x 17"). To the left of the chart, I tape velcro circles (I like the self-adhesive kind). I laminate my voice level arrow and put a piece of velcro on the back. Throughout the day, I move the arrow up and down the Voice Level Chart, to communicate voice level expectations to my students.