Materials: none

Sometimes is becomes apparent in the middle of a lesson that the students in your class are done being attentive.
Your efforts to teach a wonderful lesson are in vain. Close your book calmly, and sit down very sweetly, (preferable in one of the kids little chairs if you can).
When the students realize you've stopped speaking and are waiting for you to discipline them, just smile.
Then announce the you have just realized that today is a holiday for Primary teachers, and you shouldn't be teaching on your day off.
Pick a child to finish the lesson (or 5 minutes worth of lesson material).
Give him the lesson manual, point out where they could continue the lesson, whispering suggestions and encouragement.
This is not intended to be a punishment, but can be a successful teaching moment for the student, who will hopefully develop greater appreciation for your devoted efforts.