For me Positive Behavioral Expectations because behaviors can be difficult at time to manage.  Sometimes student misbehave in class especially during group activities.  It is sometimes hard for them to follow instructions and steps given to complete a given task or sometimes even participate fully in group activities are a challenge. I believe that it is during group activity it can be difficult to observe because teacher have to be going from one group to another. So therefore we need to emphasize rules on a regular basis.