Create a plan of action that defines rudeness, and decide on what responses by teachers are appropriate when a parent or group of parents acts rudely or out of control. Differences in opinion are natural; for example, heated arguments can begin during a sporting event, especially after an opposing team commits a foul. Make sure your action plan covers as many possibilities as you can for what might go wrong.
Announce to everyone present that rudeness, such as yelling, fighting or negative comments, is not acceptable and will not be tolerated. Be clear about your expectations for behavior during the school function, such as reminding parents to be supportive and friendly. Remind everyone that parents who violate the rules will be removed.
Reinforce the rules consistently during the school function. For example, repeat the rules during halftime of a sporting event. This reminds spectators of the rules and reaches those who have arrived late. State the rules positively; "This is a friendly reminder to everyone that ..." is a positive way to start the announcement.
Recruit parent volunteers to help out during the school functions. They can help welcome the other parents, enforce the rules and alert school staff in an emergency. Instruct parent volunteers to remain positive when enforcing the rules.