The concept is simple. You can ask a question then throw the ball to any student of your choice to answer. This is great as you better believe every student will always be alert and ready just in case that ball comes flying their way! Now depending on the activity, the student could throw it back to you ready to throw at someone else, or instead they could then ask another question and throw to the next student! This could create quite a fun question chain! You could also get students standing during question time and then ask them to sit down after answering to avoid the same people taking part.
This is great fun and all students get really excited! However, I teach teenagers and I know what they can be like, so I just like to lay down some ground rules first. They mustn't throw the ball too hard and need to keep it low enough to miss the ceiling lights but high enough to go over peoples' heads. I also like to make a point to encourage people to be polite if someone accidentally misses the ball, and if anyone is seen teasing someone or throwing purposefully roughly will be banned from the ball for that lesson. I've not had any problems as of yet, but I do feel the need for the warning as having permission to throw in a classroom is a novelty and gets them a bit over excited the first few times!
So bring new life into your questioning routines in your classroom and watch engagement soar! (Haha)