Sarah, a 15-year old girl, told us her story.

"It all started when I fell out with a girlfriend in my class, six months ago. Some other girls were stirring and told her that I'd been gossiping about her behind her back. It wasn't true, I'd always liked her, but she freaked out and started giving me the silent treatment. I tried to talk to her about it, but she just blanked me."

"My friend's older sister was about as different from her as you could get - it was hard to believe they were from the same family. She was funny and kind, where her sister was loud and harsh. She was always in trouble with the Year 11 teachers and hung around with the skivers. They were always smoking and drinking."

"She obviously told her sister what had happened, because she started to give me major grief. I had to stop walking to school through the park, as she'd hurl abuse at me. One day, I was standing with my friends during recess when she came up behind me and chucked a can of Coke over my head. It was so humiliating - everyone laughed."

"About a week after that, I was in Physics when my phone rang - I snuck a look at it under the desk. It said 'Go home. I've killed your cat.' I don't have a cat, so I knew it wasn't true, but it was such a shock I dropped my phone and felt like bursting into tears. Two minutes later my phone went off again. It said, 'Watch your back because I'm going to kick your head in soon.'

"From then on it was constant. Not a day would go by without some evil SMS. My friends knew and some of them were sympathetic, but as time went on they started to say, 'What's your problem, it's only an SMS, at least she's not beating you up'. I really don't think they understood how awful it felt. I was always on edge, wondering what mean thing they'd say next."

"Eventually I told my mum. She was brilliant. She got onto the phone network and got them to give me a new number. Although I still had to deal with my friend's sister and her friends shouting bitchy comments at me, at least once I'd left school I could breath a sigh of relief. Now I only give my number to friends that I trust 100%. SMSing has become fun again. When my phone lights up I don't feel that niggling dread in the pit of my stomach anymore."