Bully gives a voice to the victims of what is all too often shrugged off as something that is part of growing up.

Hirsch spent a year following three teenagers over a school year in the US to find out how bullying affected them and their families.

Hirsch, who directed the Sundance award-winning Amandla!: A Revolution in Four Part Harmony about the role of music in the South African struggle, has a unique ability to make his young subjects share their stories, and this allows him to get close to them in their day-to-day lives

While Bully is an activist film, the voices of subjects and their parents save it from being too heavy-handed . To watch the parents of children who have been driven to suicide and to hear a 12-year-old boy say that, after weeks of abuse, he feels like he belongs somewhere else, is to understand that bullying is much more than a part of growing up. There is no attempt to ask the bullies why they do what they do or to examine the phenomenon within a broader social context, but Hirsch has made it clear he is using this film as a vehicle for change.

A child like 14-year-old Ja'Maya, who goes from being an A student to serving time in a juvenile detention centre after taking a gun out on her bus as an exasperated last resort against her tormentors, needs to know that she isn't crazy - the system that allows bullying to reach such levels is crazy.

It's uncertain whether the film will deliver on its promise to create a movement against bullying here, as it has tried to do in the US, but it leaves you feeling that the idea that your child is safe in school is an illusion .

'Bully' opens at cinemas today

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