I always tell my students that there is "nice teasing" and there is "mean teasing," and you have to learn to tell the difference to react appropriately.
"Nice teasing" usually comes from someone who cares about you (a good friend, for example). This friend may tease you to help you laugh about a difficult situation and take things less seriously. Some who is "nice teasing" will laugh WITH you, not AT you. It's important not to take "nice teasing" the wrong way and become overly offended or sensitive. Laughing at yourself and enjoying good-natured ribbing is a part of having fun and enjoying relationships.
"Mean teasing" is different - and the difference is usually pretty obvious. Kids who are "mean teasing" are usually not your friends, might be older, and usually have more "social power." Kids who are "mean teasing" are trying to embarrass you. They are laughing AT you, not WITH you. If this goes on for a long time and isn't an isolated incident, it can be called "bullying." However, it's important not to call the occasional mean tease or a regular conflict "bullying."
Simon's Hook, in particular, provides practical strategies to help empower students to handle teasing on their own. The strategies may not seem conventional, but they help students to not internalize the "hooks" (teasing) and show the teaser that it's not so easy to ruffle their feathers:
1. Do Little or Nothing (don't react)
2. Agree with the teaser (even though you really don't!)
3. Distract (change the subject)
4. Laugh or Make a Joke
5. Stay Away from the teaser
Simon's Hook also provides lots of teasing examples to "practice on" using the different strategies.
It's important for students to know that if they feel unsafe or afraid (particularly if the teasing turns into physical aggression), they should ask an adult for help. Encourage conversation with your child, and if you're concerned, contact the school. Your child's teacher, the principal and assistant principal, or the social worker are all great people to talk to about teasing.