You'll only shame him. No name-calling or snickering allowed. Perhaps the most important rule is not to razz your child in public. By observing limits when you tease, you show your child how to clown around in a way that doesn't hurt people but instead conveys affection. Add your comments to the bottom of this page.
Children are notorious for noticing everything, and are usually quite vocal about it.
It can also be a way for them to take control of a situation. For example, your child may tease someone so she runs off crying instead of taking her turn on the slide. Then your child gets to go first. You can help your child develop his sense of empathy so he won't tease someone else. Whatever the reason for the taunts, research shows that talking to young children about the effects of their behavior does in fact help them develop the ability to put themselves in another person's shoes, though maybe not overnight.