Time needed: 1-3 min
Why? Everyone is using the new technological inventions, mobile phones are common, everyone knows how to use it.
When? Any time while introducing a new topic or in the reviewing stage.
How? Give the students a task to solve and if they have a question they have just one telephone joker, let then send to some friends one sms or a short call to ask that question. They will have some fun while doing it and they need to think clearly which friend can know the correct answer. They need to think about the topic and who is connected to that topic from their friends.
Any risk? Yes of course some students will use the chance that they have their hand phone for a moment in their hands to send a private sms, just let them do it, its also a moment for the students to relax their mind and its just 1 minute, then everyone has to switch of the phones again. Or use your own hand phone if you just give the whole class just one joker.