The initiative, ChildLine in Partnership with Schools (CHIPS), piloted in 90 schools over the past two years, encourages pupil mentoring, anti-bullying programmes and fund-raising events to help ChildLine to spread its message.
It now has the Government's seal of approval - and will be launched next week by David Blunkett, the Education and Employment Secretary.
One in eight children who phones ChildLine is worried about a friend. The CHIPS project encourages pupils, with the help of teachers and parents, to become more aware of each other's needs.
The pilot schools will praise the scheme in a launch at Southgate School in Cockfosters, north London, where lower-sixth pupils are CHIPS team members. They give talks in assembly, raising awareness of the importance of talking through problems - and are available to do just that.
Oxted comprehensive school in Surrey has 1,900 pupils and two CHIPS projects. Last March, 20 pupils were trained in listening skills, and the school set up a peer -support scheme to help to tackle bullying. It has developed a befriending scheme for all new pupils. Now all Year 7 children have an older pupil mentor to turn to.
Deryn Keynton, head of a school house, said the measures had brought about a culture change. "There is now a feeling in the school that bullies are really rather sad and that bullying is not a cool thing to do."
Mentoring means new pupils have "someone to sound off to and seek advice from without any fear of being stigmatised. It is very encouraging that older pupils are so keen to get involved."
Manchester Grammar School set up a peer-support project after a ChildLine survey found that boys tend to bottle things up. Forty boys were trained in listening and communication skills.
Neel Shah, a sixth-form CHIPS representative, said: "Peer supporters learned to understand that what they're told has to be confidential, unless the problem is so serious that someone else has to know. They also have to be aware of the limits of their own expertise."
Maggie Turner, CHIPS project manager at ChildLine, said many schools are already embracing pupil mentoring.
"We are not going to go into schools and tell them what to do. The idea is that teachers adapt what is taught to fit into the schools' own structures. "