How I Use It
I use Kahoot to quiz my students on the previous night's reading assignment, review key points from a previous day's lesson, or to survey their opinions on current events. The quiz format is very competitive, posting the high scores publicly. I sometimes use the survey format instead, just to reduce the level of crazy in my very enthusiastic sixth grade class. Either provides me with a quick snapshot of their understanding and I can still share the correct answers with them as we go along.
This is a simple and very engaging tool. It is probably most effective used regularly but sparingly -- kids love the format but the limited text fields for questions and answers prevent the teacher from asking anything of much depth. Could be useful in an advisor group situation to survey student opinions on controversial topics as the responses are posted anonymously.