Up to £22 million will be made available over the next three years to improve therapy for young people with mental health problems, Nick Clegg has announced.
The Deputy Prime Minister said "too many young people suffer in silence" and it was important their illnesses were "not simply swept under the carpet".
The extra funding is intended to ensure more young people in England can be helped, as well as providing access to a wider range of psychological therapies.
These include cognitive behavioural therapy (CBT), a type of talking therapy, and family group therapy.
Treatment will also focus on major issues such as eating disorders, depression, self-harm and attention deficit hyperactivity disorder (ADHD).
Some cash will be spent on extra training for NHS staff and those who work with young people such as teachers, social workers and counsellors.
Figures from the Department of Health suggest one in 10 children aged five to 16 has a clinically diagnosable mental health problem.
Self-harming and substance abuse are more common in children and young people with mental health disorders - with 10% of 15 and 16-year-olds having self-harmed.
Half of adults with a long-term mental health issue experience their first symptoms before the age of 14.
Clegg said: "Too many young people suffer in silence with mental health problems.
"This is vital investment that will give children the very best tailored treatment to restore them to good health, so that their illnesses are not simply swept under the carpet.
"With one in 10 young people suffering from a mental health problem, we cannot let this issue drift or rely on adult services as a cure-all.
"The money we are investing today will work specifically for children on therapies that are proven to work.
"Mental health must have the same priority as physical health.
"Giving children the treatment they need as soon as they need it will help ensure that millions of children suffering from a mental health problem will have a fairer opportunity to succeed in life."
The new money will be spent on the Children and Young People's Improving Access to Psychological Therapies (IAPT) project.
YoungMinds chief executive Sarah Brennan said: "We are delighted that the g Saovernment has committed to further extending IAPT services for children and young people.
"Intervening early when a child or young person starts struggling to cope is proven to reduce the likelihood of that young person developing much more severe and entrenched mental health problems."
Up to £16 million of funding over the next four years will also be invested in the Time To Change social marketing campaign to tackle mental health stigma and discrimination.
Sue Baker, director of Time to Change, which is run by the charities Mind and Rethink Mental Illness, said: "We know that mental illness is still a taboo subject, and this is very much the case with children and young people who tell us that they don't feel able to talk to their friends, families or others if they are struggling."
She said reducing stigma will mean more young people access services enabling them to "be active citizens without the barriers of discrimination and misunderstanding".