When I teach I am calm and assertive and I am quick to correct any unwanted behavor from my students. If I see someone folling around I am quick to let them know I am aware of what they are doing. I give them a short gestured look of dissaporval. If the behavor continues I punish them with push ups and continue with the lesson leaving it up to them to catch up. This usually makes them more observant to what other students are doing because they now feel left behind. Believe it or not they are now encouraged to listen and observe for directions.
If a group of kids are causing a distraction I separate them. I remain calm at all times, never let them see you sweat. When ever possible interact with them, pick out students to demonstrate techniques, give positive comments, reroute that excess energy.
In our school the running comes prior to class as part of the warm up prior to stretching.
You cannot allow a student to disrupt a class. You see the bad behavior happening, and you handle it, don't let them break your stride. Keep things moving.
If it comes to the point where the student is just so far gone that he needs to be removed from class for the day. DO IT, remove them. And discuss it with the parents. Don't let the other students suffer, and you keep face in their eyes. Seeing how you handle things immediately they will not act up themselves.
Of course staying calm takes lots of practice, you cannot how anger or disappointment. You want to remain assertive and authoritative. Oozing calm confidence.
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"Poor is the pupil who
does not surpass his
master" - Leonardo Da
Vinci