Urgent action is needed to tackle the reasons why more children are committing violent crimes, according to a West Yorkshire Young Offenders Institution.
In its latest report, the Independent Monitoring Board (IMB) at HM YOI Wetherby made the call to the government, saying the number of violent crimes has risen among young people.
The prison holds about 240 "extremely challenging young people" aged between 15 and 18, of those 52% are charged with violent offenses.
The report says: "Last year we asked what's being done to reduce levels of violence among young people, this year, we see no evidence of improvement and the number of violent crimes has increased, so ask the same question."
The report also called for answers to what's being done to reduce the time taken to fill vacancies at the prison, saying delays "seriously compromise the establishment's effectiveness".
The Government said a special unit will soon open at Wetherby for prisoners with mental health problems and more staff have been hired to run it.
A spokesman added: "The Government is investing more than £220m into early intervention projects to stop young people from committing a crime in the first place."