By Rory Cellan-Jones
Technology correspondent, BBC News
Children's own film about their love of mobiles
How big is your mobile phone bill? Have you ever felt uncomfortable about some of the text messages you receive?
And what's the attitude of those in authority to the use of mobile phones when we should be working?
All of these questions have probably been asked in offices across the country - but they were also the issues investigated by students at Marden High School in Tynemouth as their contribution to the BBC's School Report project.
They started by carrying out a survey of mobile phone use at their school.
Of the 920 pupils, aged between 11 and 16, responses came from 519, and only three did not have their own mobile phone.
This was also a very advanced group of phone users. They were asked whether they had text, photos, videos or music on their phones, and 460 said they had all four.
I was getting nasty messages from a boy I gave my number to - but it stopped when I confronted him
Survey uncovers text bullying
We then sent three teams of two students out to investigate each issue. They were helped by others who operated cameras, some of them using mobile phones to film part of the report.
The first team concentrated on cost. They found that ,while most pupils were only spending between £5 and £10 a month on their mobiles, a few spent as much as £40.
One girl, Katy, told the team that her £40 bill was not unusual.
And guess who's paying the bill? Two thirds said it was Mum and Dad, though a few had to contribute if they went over a cost limit.
The survey had shown that about a quarter of students had received bullying texts, and the team investigating that issue found that two pupils willing to talk about it.
Stephen told them: "I was getting nasty messages from a boy I gave my number to - but it stopped when I confronted him."
Kayleigh had gone to see her head of year with her mum after getting abusive messages from an older boy - and the bullying had quickly stopped.
Our team concluded that children needed to know that they could take action against the mobile bullies.
The final issue the Marden High School news teams confronted was what teachers thought of mobile phone use.
The Head Teacher David Stainthorpe had told us that there was a school policy effectively banning mobiles from the premises but "if we had a search we'd find 1000 phones amongst the 920 pupils."
The teachers were asked to list their concerns and they had plenty - from "happy slapping" and the sharing of explicit images to inappropriate videoing of teachers.
Deputy head Joan Bloomfield said, that when confronted with examples of abuse, "It's very important that the school takes a very firm stance and steps in quickly."
But this school is a specialist media college - as the Head puts it "our specialism is the creative use of digital media" - and teachers are beginning to think about ways of using mobile phones as an educational tool.
In one class, students filmed an animation on a mobile phone. And of course during the filming of their school report, the pupils made great use of mobile phones, filming some of the shots you will see in their report for the Six O Clock News.
So what had they learned?
Rosie told me that while teachers seemed to think there was more bad than good about mobiles, she thought they were very useful for keeping in touch with parents.
Her friend Katie agreed that she'd feel lost without her phone , and then there was a chorus from their neighbours: "I couldn't live without my phone".
On 13 March 2008, hundreds of schools are making and broadcasting their own video, audio and text-based news with the help of the BBC via the School Report project.
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