Arm yourself with this toolkit, and you'll be better prepared to head off any potential classroom disasters. Help participants know what is expected by giving them a job description. Another stage-setting procedure when introducing potentially unpopular policies is to make clear in the beginning that the course content is not just a suggestion. It is, in fact, a decision on the organization's part that has been considered, discussed, and settled. Make the problem participant the team leader.
People often can be disruptive in a classroom setting because they crave attention.
In this case, they are not driven by malice or hostility, but by the desire to be noticed. Communicate without words. There are many non-verbal signals we can use to communicate to a participant that behavior is unacceptable. No law requires you to respond to every statement a participant makes. Then move on with your next agenda item.