Children are not being taken seriously when they report violent and sexual crimes, the Government's victims tsar has warned.
Criminal justice agencies are at risk of failing youngsters who feel they are being let down by the system that is meant to protect them, according to Baroness Newlove.
The Victims' Commissioner will publish a review on Wednesday which found children and teenagers were made to feel like criminals themselves, accused of wasting police time or simply not believed.
Citing previous inquiries into the Rotherham and Jimmy Savile abuse scandals, the report says: "It seems that lessons are still not being learnt about believing young victims when they come forward and taking them seriously."
Twelve females aged between nine and 17, or their parents, were interviewed about the handling of reports of sexual or violent crimes.
Many of the children and their families did not feel they were treated with "dignity and respect", with some feeling they were not believed nor taken seriously because of their age, the report found.
Girls described feeling as if they had to "prove themselves", with one reporting that she felt like "a test subject - a monkey in a cage to be prodded".
Many of the youngsters who took part in the review felt they were not believed by police, social workers, teachers or by society as a whole and would be reluctant to report a crime if anything happened to them in the future.
Participants were also frustrated at a lack of information about the progress of their case, and on the whole they did not receive or were not informed about all of their entitlements under the Victims' Code.
In one rape case a teenage girl was interviewed by male officers on three separate occasions despite asking for a woman officer each time, according to the report.
Baroness Newlove said: "These children and young victims feel let down by the system that is meant to protect them. It is time attitudes towards them were changed.
"I want to see agencies working together to make sure young and vulnerable victims feel supported through the criminal justice process.
"They deserve to be taken seriously, for their allegations to be thoroughly investigated and to be treated with dignity and respect."
Some areas of good practice were highlighted in the review. It found that most of the children had an adult with them when interviewed by police, and were informed about special measures to help them give evidence at court.
The report said the review "has a limited sample and as such the conclusions cannot necessarily be generalised to the whole population".
A spokeswoman for the NSPCC said: "The review pulls into sharp focus how disgracefully our justice system continues to fail young witnesses."
The Ministry of Justice said it is "putting children first at every stage of the justice system" and will publish a victims strategy by the end of the year.
A spokesman added: "While we welcome Baroness Newlove's report and will consider its findings carefully, it is important to note that they are based on a very small sample of victims' experiences of the criminal justice system."
Olivia Pinkney, National Police Chiefs' Council lead for children and young people, said: "Children are children first and foremost. As a service our duty is to stop harm and keep people safe no matter what their age or background.
"While it is disappointing to hear about cases like this we know the police response to young people has moved on hugely in recent years and we always aim to put them, and their wellbeing, at the heart of what we do - focusing on the most vulnerable including children in care."