Professors Richard M. Felder and Rebecca Brent (North Carolina State University) discuss options on dealing with classroom management issues of late attendance, sleeping in class, and talking to neighboring students.
As they note, your response should depend on two things: Is the offending behavior distracting the rest of the class from your teaching and is it the first time or an ongoing problem?
Assuming the behavior is disruptive, they state you can react in an aggressive, passive, or assertive manner. The best approach? Be assertive, not aggressive. “Calmly and clearly stating the problem and asking for what you want is an assertive response.”
You can read their tips here: