I visited Kahoot and played a few Kahoots that were on the site to get a feel for it. I can see how this would be awesome if you had a 1 to 1 device classroom. It would be great to use during instruction to check for understanding and poll students. I can see this as at any point during the unit. Probe for prior knowledge as we begin a unit, checking for understanding as we progress through the unit or even as a review for a chapter test. My professors have used Kahoots in my classes, I found them fun and engaging.