Traffic light system for giving warnings for misbehaviour in the classroom, in a calm, non-confrontational way. Green cards for children who are working hard (especially if this out of the norm!); orange for a first warning and reminder of the golden rules; and red for a final warning before sanctions arise. Children receiving warnings can earn a green cards by getting back on task. Can be linked to class reward system, e.g. team points etc for those with green cards at end of lesson.
I like this system. I have a traffic light display where each child begins the lesson in green. If they need to, then they move up to yellow. If it continues they move to red where there is a consequence to match the behaviour choice. If they modify their behaviour, then they can move back to green.