More than a third of juvenile offenders went on to commit another offence within a year, figures showed today.
But in some parts of England and Wales, this rose to almost half, according to the latest Ministry of Justice (MoJ) figures.
Almost 36,000 of the 110,000 young offenders aged under 18 who were cautioned, convicted or released from custody between July 2009 and June 2010 committed another offence within 12 months.
They committed more than 100,000 further offences between them, an average of almost three each, the figures showed.
But the reoffending rates varied considerably in youth offending teams across England and Wales - from Merthyr Tydfil, in South Wales, where 48.8% of the 160 offenders committed a further offence, to Bracknell Forest, in Berkshire, where the figure was 23.3% of 103 offenders.
Officials said a large part of this variability "reflects the mix of offenders" who are managed by the different teams.
The figures also showed that, since 2000, reoffending among juveniles who received a community penalty rose by 5.5%, while falling by 7.5% for those who received a custodial sentence.
Juliet Lyon, director of the Prison Reform Trust, said: "The number of children committing offences over the 12 months covered by the report fell by a fifth, the number reoffending by 17%, and the number of further offences by 15%, significant reductions which reflect the success of concerted efforts by police, youth offending teams and others to tackle youth crime.
"Marked geographical variations in reoffending indicate that there are lessons to be learned from high-performing local authorities and show we can and must do more to help children out of trouble."
A Ministry of Justice spokesman said: "Overall, reoffending is falling and the majority of criminals do not go on to commit further crimes. However, we believe reoffending rates are still too high.
"We are introducing reforms to break the cycle of youth offending including robust intervention, increasing the use of restorative justice and supporting local programmes which better tackle the root causes of youth crime and reoffending.
"We also want to free up practitioners to give them greater discretion in tackling offending."