I use voice levels all day long while working in groups, whole group instruction, etc. Once you model the voice levels for your students it really does work.
If they get too loud, to a level 4 for example, I will move the arrow up to the 4 & say "you are here & I need you to be here" & move the arrow down to a 2 or 1. The visual really helps my students more than just verbally saying it. Check out my other Peace themed items in my store. If you like this sign & would like a different theme please email me @ firstname.lastname@example.org to make a request.
I am a first grade teacher & absolutely love my job! This is my 8th year teaching first grade. I used to teach kindergarten for 2 years as well. Check out my blog http://www.seustastic.blogspot.com for TONS of ideas & freebies!