You asked

Bullying: What can you expect from the school?

If you report an instance of bullying to a school regarding your child, you can expect that the matter is dealt with it a serious and professional manner. Every school must clearly follow the instructions contained within the anti-bullying policy document. Parents can request a copy of this from the school so they can monitor progress.
The school will generally deal with any incidents of bullying by meeting with the students accused. In many cases, a verbal warning is all that is needed to end the bullying as long as the situation is monitored. If this isn’t enough, the school will have to take things further by either meeting with the bully’s parents or by proceeding with disciplinary action.
 It’s important that the school takes your complaint seriously and reacts appropriately. If you are not satisfied with the way the school is dealing with the situation, you are entitled to take your complaint further. 

More questions

Children who bully want to exert control over their lives-even if it's just making someone else's life miserable.
This can be a difficult realisation to come to but there are some signs to watch out for which could indicate that your child is a bully. 
Your child's school should have a very clear policy on how to deal with bullying.
In recent times, cyber bullying has become all too common. 
There are lots of things that you as a parent can do to help prevent and reduce the chances of your child being bullied.
Bullies choose their victims for many reasons and the sad fact is your child can be bullied simply by being in the wrong place at the wrong time.