to some classroom behaviours such as what you've encountered.
My thought about it. I'd suggest you focus on what you want student to do rather than what they did wrong. For your case, I'd emphasis "I(!) want students to focus on their learning and I (!) dont want chitchat disturbing my classroom and my(!) teaching" (rather than 'you did..wrong.'). The boy would have no excuse to say you 'pick him up'.
But before that, you can do other things to stop this.
Dont just call him in a distance 'dont talk please'. Go on your teaching but walk toward him and stand right next to him, lean your body over and keep your eye to his eye and go on your teaching as if you are teaching only to him, until he stops talking (if it involves only on person talking). You dont even need to say anything apart from your teaching. "Teacher's evil eye" is a very powerful tool:-)
You can call his name and ask if he can help you to do something (find any excuse to ask him to help).
You can stop talking, until classroom is so quiet that only their chitchat is only source of noise.
You can ask the classroom do to some private work and go to get him away from other students in the name of 'helping me' to have a short talk with him, requiring him not disturb the classroom.
Or, even before that, you can discuss the classroom rule with them, make them to make the rules (especially those who tend to cause the problem) and ask them to help you maintain the classroom order.
what you can do afterwards:
Or, when the boy is still in a bad mood, ask him to choose what he'd like to do to disturbing other kids. If he still refuses to cooperate, give him choice: stay quiet in the classroom or go to principal's office. (hopefully you dont have to do this). if he choose principal's office, then send him away and go on your class.
Important, do all those in a assertive but not emotional way. It is not easy, pat pat:-)
