This is my favorite game-based assessment tool, hands down. I have employed Kahoot in my classroom to help students review for formative assessment for the past year and a half, and it has truly been a hit. Kids now request the game by name, as they can't get enough of it! This web-based assessment software emulates the classic tavern-style trivia games that many of us teachers have played in the past- some as recent as this last weekend, I would imagine! :-)
First, it is important to note that every student will need access to a wireless device or computer connected to the internet to participate in the game. As for the game, each question is accompanied by a timer, and the faster that participants answers the question correctly, the more points ("Kahoots") they are awarded. That's it. Simple, effective, and fun! Try it today and your students will thank you, I promise!