Prison inspectors are calling for improvements to be made to services for juveniles at a young offenders' institution in Greater Manchester.
The calls follow an 11-day inspection of HMYOI Hindley in Wigan last summer.
The report, by Her Majesty's Inspector of Prisons, showed discrepancies in the level of services for juveniles aged 15 to 17, and young adults aged 18 to 20.
But it also praised improvements in a number of areas since the last visit, especially in mental healthcare.
Issues highlighted included juveniles having a higher number of assaults and use of force - with incidents of broken bones happening on three occasions following the use of force.
Concern was also raised over "calm-down" cells for juveniles which, the report claimed, did not have proper safeguards and were "in effect unfurnished cells".
The inspection also revealed that education for juveniles was undermined by poor punctuality and that they spent some "unproductive time" cleaning on the wing.
Anne Owers, chief inspector of prisons, said: "Overall, this is nevertheless a report on an establishment that has made progress in trying to manage a diverse and often challenging population.
"Some aspects, such as personal officer work, activity levels for young adults, and mental health support, are models of good practice, and are achieving some positive outcomes."