Learn to fight?
            Now what has THAT got to do with bodybuilding!!???            
Well actually, it's got quite a lot to do with bodybuilding. Firstly I'm going to teach you to defend yourself. I'm NOT telling you how to start fights and if you do, you'll have ME to answer to :-)
Although you would probably think that the opposite was true, bodybuilders are often the target of abuse. Because of their size, or the fact that they' re proud to be who they are, people with something to prove often bother them (that's my experience anyway). A lot of people get into bodybuilding so that they do not become the target of others.
By learning to defend yourself, you can, obviously, defend yourself, but the ability to defend yourself will go much deeper than that. From following a basic program I will set out for you below, you can turn your body into a fighting machine, capable of handling the biggest meanest most determined dickhead you can find.
You will experience greatly increased self confidence, which can be beneficial to bodybuilders both in competitions, in the weight room and out on the streets. You will learn self discipline which, although most bodybuilders already have good self discipline, will help you to never skip a workout or break your diet ever again!
As well as this, a lot of bodybuilders bodybuild just for the sport, or to look good. Obviously this is not good for motivation, as it really helps to have something, such as a competition, to work towards. If you are fighting competitively, it will give you a real mental boost in the gym.
From training regularly, you can also increase your stamina greatly, which will help your fat burning cardio, as well as with competitions if you enter any. It will also help at school or in any sports events you enter. There are not many things as tiring as 3 minutes of boxing.
I recommend that you follow the Royal Marines fitness schedule I have detailed in one of my other articles to build up your physical stamina and muscle endurance, as these are important especially in the ring as well as on the streets.
Below are most of the things you will need to know to defend yourself:

So what do I do if I am threatened?

The advice you would get from (nearly) any professional would be to run away. Running (or walking) away is the smartest thing you can possibly do if threatened. If you are somewhere where people don't know you, then walking away is definitely the smartest thing you can do. Even if it is somewhere where you know the people, they will not think less of you for walking away from a fight. Only run if you have to though - if you can walk away from a situation, you are actually LESS likely to be followed. If you run, you appear scared and an easy target. If you walk, the "enemy" will be a lot less sure of how much of an easy target you are.
If more than one attacker is threatening you, the ONLY real option you have open to you is to avoid the fight altogether. Real life is not like the films - you can not sensibly defeat more than one opponent at the same time. With these stories you hear of people taking on multiple attackers, the people involved almost always attacked one at a time. Very rarely is someone fast enough or strong enough to fend off attacks from more than one person simultaneously. Also, if the attacker is carrying some kind of weapon such as a knife or a gun, the only thing you can do is run like hell.
The problems come when you are cornered, too tired to run any more, or the situation in unavoidable (for example, the whole school is watching). This is what I am teaching. As I said before, do NOT use any of these techniques to start fights.
It might be worth noting that peoples' reputations are usually far outweigh their actual capability. A lot of people look "hard" and act "hard" but very few of them actually are.
Anyway, on to the lesson:
The first thing I am going to tell you is that 99% of a fight is mental. Physical capability and skill do come into it, and they do matter, but they do not usually determine the outcome of a fight. Only if no side is particularly wound up, or both sides are equally wound up, will the outcome of the fight be determined by these factors. There is also a certain amount of luck involved in any fight, and you have to bare this in mind. No matter how good at fighting you are, you can ALWAYS be beaten! Don't get involved in any fight you can avoid.
Mental attitude, though, is the thing that wins fights. If you think that you might fail, you WILL fail. If you are certain that you will win, you MIGHT win. This is the main part of any fight. Do not back down and psyche yourself up.
Also important are the following:
Your stance
Stand sideways. I will assume you are right handed and tell you to stand with your left foot forward. If you are left handed, you will have to stand the other way around. Stand as if you are on a surfboard and make sure that you can lock your back leg - this will mean that the attacker can not push you over easily. Do not grip your fists, as this does nothing for you. Instead, hold a very loose fist right up until you actually strike.
Your technique
The technique is simply this - "Hit first, hit hard, hit fast, and keep hitting". By this, I mean hit as hard as you can (although it doesn't matter too much how hard you can punch), hit as fast as you can so that your opponent does not have a chance to get his act together and strike you back. And keep hitting! The biggest mistake that most people make is to stop hitting when their opponent looks beaten. Unless he is lying on the floor or KO'd, he is probably perfectly capable of hitting back if you give him a chance. Practice hitting in a mirror. If it looks good in the mirror, it is probably good. Also remember to fight dirty if you are being beaten.
Your fitness can also be worked on, but as I said before, it is not terrible important.
Thanks for reading - don't abuse any of these techniques.