How I Use It
Voki is a great way to get students talking in a world languages classroom. Especially early in the school year, creating an Avatar and making it speak really helps to get students out of their shell. I found that it did take a REALLY long time, however, to enter student names into the roster so that they can all have accounts in my virtual classroom. There doesn't seem to be an easy way to import preexisting lists.
I think that this tool can work with any age group but it is probably best suited for younger kids. I also wonder if creating a speaking avatar is just a complicated substitution for getting students to just speak out loud without the help of a computer.