What can I handle by myself and when should I ask a teacher or principal to step in?

There should be nothing that you should endure on your own. As soon as something happens it is best to let someone know. If your principle is the first point of contact then let them know instantly. This is because over time it will get worse. Not only will it harm your metal health but it will also make the bullying worse. You are better letting someone know immediately because while you think you are handling it, someone may happen which cannot be solved. If not the principle then talk to a safeguarding staff member to someone who deals directly with these problems.

It all depends on the individual. I am assuming, that you mean bullying at school, and how much you can handle, and when you should get a teacher involved. Every individual handles bullying differently. One could struggle with an event a lot and badly, while the other person that goes through the same thing, may just shrug it off, and it won't bother them. I would suggest that you tell a teacher right away. But if you don't want to, then tell the teacher when the bullying gets to you, and affects you.

You can handle a piece of teasing if it happens once of twice, but if it happens more that or if it is physical you should ask a teacher to step in.

One thing you can handle by yourself is something minor like asking someone to step down whenever they are picking on you. When they start impacting you personally with crude comments or being over all rude is when you should report it to the authorities.

Serious violence (anything that scares you or leaves a bruise), sexual assault (this includes groping), or any threat of these that seems serious, take to an adult right away, whether it's done to you or someone else. Anything else, try to handle it yourself once or twice, and if that doesn't work, tell an adult. You shouldn't have to put up with bullying, even if it's not physical. If the adult tells you to "work it out yourself," try a different adult, or several if necessary.

My personal rule of thumb is when the negative effects are more then momentary. For instance, if something is bothering me for a while, but it's temporary, I'll try to handle it myself. However, if something is having a pervasive negative effect on me, then I owe it to myself to get help. If something is negatively effecting your life in general, ask for help.

Hmm. That's a tough one. I think that it would depend on the situation. If it's causing you any stress, worries, emotional or physical pain then thats when you should ask a teacher, principal or any trusted adult to step in.

This situation depends entirely on yourself and how you cope emotionally. If the person can distance their self enough from the bullying to not get personally affected by what they say and try to talk it out, then the situation might not need to be escalated. Note this is in the regard for bullying; bullying is verbal, any physical mockery, act or contact that makes you feel threatened is Physical Assault and is ILLEGAL. This should be taken to an authority i.e. a teacher or other impact adult immediately.

If it is like a little conflict between a friend than that can be something you can resolve together most times teachers or principals are in need is when it comes things like internet bullying, bullying in person verbally, physically or even in class by passing mean notes from paper wise.