Use of verbal abuse ranges from the ubiquitous use of the word gay to denote anything someone does not like or sees as broken to use of specific slurs such as fag, dyke, fudge puncher, rug muncher, lemon, queer, batty boy
Cyber bullying is also prevalent and can take the form of bullying on the mobile phone, texts, filming abuse and sending it out, and abuse left on social networking sites.
The behaviour can be from refusing to sit next to someone and that can be blatant or subtle.
The best way of dealing with that is to have seating plan that you change regularly and insist on.
Refusing to pick certain people for teams or groups
Giving wrong information or refusing information
There is a very useful model with power point by Gordon Allport that explains these steps linked to an actual case which can be used in an assembly or lesson See