It's not a simple matter of keeping their attention. The fact is that none of the "audience" even wants to be there but they have no choice. You see my plight?
Oh, one of those.
Got an emailed "good news slip" from the school about my 16yo lad today (he likes to pretend he doesn't take school seriously and never does any work and spends all his time drinking and taking drugs, so the school really pisses him off when it keeps sending these notes saying how well he's doing).
Neither the teacher nor the kids wanted to be in the PHSE (or whatever it's called this week) lesson, now did they. So the teacher ... got them to make a snakes and ladders game about sexual health. You can imagine what they produced, particularly the graphics! Bit of inventiveness on the part of the teacher kept then quiet and amused for the lesson, and just possibly they actually learned something.
(Resulting in a discussion over the family dinner table about whether "getting pissed" should be a snake or a ladder, the Macbeth door keeper sketch and so on.)