Having other pupils who can support those bullied really helps to stop it happening, says Alison O'Brien who works with the National Society for the Prevention of Cruelty to Children (NSPCC).
Thousands of schoolchildren as young as six have already been specially taught how to help.
Bullying
They learn how to be a "go-between" or counsellor so they can sort out problems between those who are bullied and the bullies themselves.
And they try to find out why there is a problem in the first place.