Stand next to the student who is causing a disruption. If the child is talking, passing notes or creating some other mild disruption, simply stand next to her and continue instructing the class while doing so. The child will be aware that you have noticed her disruption in an unobtrusive way that does not add further disruption to the class and will get back on track.
Infuse humor into your instruction. If you notice that a student is being disruptive, stop your lesson briefly and tell a joke or insert a comical quip into your dialogue. Attention will be drawn back to you and you can pick up where you left off.
Provide the student with a gentle reminder. Politely inform the student that he should be listening, that she should not be talking or that she should not be doing whatever it is that she is doing. Don't draw too much attention to your comment; simply state it and then carry on with your lesson.
Remove the student from the classroom. If the student is exhibiting extreme behavior or is continuously disrupting the classroom, politely ask him to step into the hallway. After you have completed your lesson and have engaged the rest of your class in an activity, step into the hallway yourself to have a conversation with the student. Explain why you asked the child to leave the classroom and ask him what may be bothering him. Offer advice and let her know you are there for him if he needs guidance or an ear to listen, but make it clear that disruptive behavior will not be tolerated and cannot continue.
Schedule a conference. If the child's behavior has reached a level of disruption that you can't control, arrange to have a conference with the student and a parent or guardian. Discuss the student's behavior in the conference and try to come to the root of the problem. Offer advice, suggestions and support, but be firm and let the child and the parent or guardian know that the behavior will not be tolerated. Create a behavior modification strategy to use with the student to help him try to control his behavior. For example, offer points and a small reward if he exhibits good behavior over a period of time. Discuss consequences for continued disruptions and make sure the parent or guardian is on the same page as you to help steer the child on the right track.