Ask the child what he's feeling angry about. If he's having a dispute with a friend, you may be able to mediate and help the children solve their issue before his anger escalates.
Remove the child from the situation that's angering him if he's getting more upset or violent. Take him by the hand or pick him up and take him to a quiet table or corner of the room. You can also set up a special corner to take children to. Place pillows on the floor. Hang pictures of children displaying different emotions on the walls.
Explain to the child that it's okay that he's angry, but he needs to calm his body down. Tell him you can't help him until he's calm.
Help him calm his body by having him count to 10 or take deep breaths. Ask him to look at your face. Model these calm behaviors and ask him to do the same thing you're doing.
Talk about what made him angry. Come up with some ideas of things he can do next time he feels angry, such as asking a teacher for help or saying, "I'm angry because..."
Hug the child once he's completely calm. Let him know that he's a good boy who just didn't make the right choice this time, and tell him you know he will try harder next time.
Take the child back to the situation that made him angry. If he used unkind words or tried to hurt another child, ask him to apologize to the other child. Sit with him for a few minutes to make sure that he's staying calm. Let him know you're proud of how well he's doing before leaving him.