In one high school last year, a group of girls bandied together and photoshopped the head of one of their peers onto a naked body.
So life-like was it, that the school wanted reason not to expel the 14-year-old. Her parents, on seeing the photograph, were devastated, dismissing their daughter's claims it was not her.
They saw the photograph. So did their friends, and their friends' friends and everyone else in the small town where they lived.
Shame coloured their days, as everyone talked about the rank pose their daughter had enacted. Quickly, their daughter stopped denying it, and in a matter of days, became a shell of the fierce and cheeky teen she had been.
After a week or two, and worried about her ongoing despondency, they sat down with her, and tried to talk it through. She could start again at another school, in another town, they said.
"But Mum, I told you it was not me."
That girl's mum is telling me the story, as tears stream down her face. At that point, she couldn’t understand how a picture could lie, but believed her daughter.
Eventually, with the help of computer technology, that family could prove the photograph was just a means of bullying a young girl, struggling to find friends at school. It had, indeed, been a brilliant photoshop.
But by then, everyone had moved on. The damage was done.
At another school, in another state, one girl photographed her own vagina on another student's phone without her knowledge. She then shared that photograph with all the young girl's contacts.
Imagine that. Imagine your daughter bouncing through the front door, to turn her phone on, and find that her father, and uncles, and friends and everyone else important to her had received that photograph, believing it was of her - and sent by her.
Why would another girl do that to someone she hardly knew? God knows - but that little one didn't go back to school last year.
One more case, before I move on. At another school, here in Brisbane, a 15-year-old jumped on her Facebook account to find that someone had created an account with her photograph, and her name - and used it to send revolting messages to all her friends.
How did that young woman walk through the school gates, two days later, once all her friends had turned their back on her, believing she had been the instigator of the abuse?
The culprit was eventually found. It was someone the victim hardly even knew, but who shared a class with her.
After surveying 1600 girls and interviewing 400 of them over the past two years, I could write thousands of words about hundreds of cases of bullying.
Cases where girls are crying themselves to sleep each night. Cases where agreements are being drawn up by schools, for the parties involved. Cases where fathers of fighting girls have met in a car park, after work, to "sort it out" with violence. Cases, such as gorgeous 14-year-old "Dolly" Amy Jane Everett, who took her own life this week, after being unable to escape the torment of bullies.
In many, many of the cases, the plot is largely the same, and so are the lessons I’ve learnt. One of those relate to school rules.
Those schools that allow teen girls to spend their lunchtime, sitting in big packs, using their phones indiscriminately risk having a bigger problem with bullying.
I don’t have the research to prove that, but I know it because of the emails that flow into my in-tray regularly from distraught mothers, and their girls.
Five or six years ago, when we were discussing high school suitable for our daughters, values and geography topped the list.
Now, it would be the social media policy enacted by the school. That would be first, second and last.
Here’s the irony, though. Some schools have actually tried to toughen their policies, but met almighty opposition - from mothers of students who believe they should be able to contact their daughters if, and when, they like.
Inspector Jon Rouse, who heads Taskforce Argos, is tough on parents of teen girls. He says, often, we have our heads in the sand, not knowing how many followers our daughters have on social media, or what the privacy setting entail.
I don't know the case behind Amy Jayne Everett's death - or even if social media was involved.
But perhaps a fitting legacy of her short life is that we all check how our own teenagers are using social media.
Mobile phones are not the only weapon used by bullies - but they're certainly a dangerous one.
Madonna King is also author of Being 14: Helping fierce teens become awesome women.
Lifeline: 131114 Kids Helpline 1800 55 1800