Setting the tone when students first approach the classroom is very important to a successful class. If they feel respected, understand the course requirements, and understand the pace of the class everything typically goes smoothly. On the other hand if you have a bad day on the first day of class, then the outcome is fairly poor. For an example if a policy has recently changed from the student's last class it causes an opportunity for animosity. Some students revert back to a high school complaining mentality and it's nearly impossible redirect those students.