Pupils at an independent school site in Halifax were found to be taking drugs and smoking by government education inspectors.
Ummid Independent School based primarily in Bradford was judged inadequate in every area by Ofsted.
In the report it revealed that action must be taken 'to address drug-taking and smoking among pupils who attend the Himmat site' which is based in the centre of Halifax
The Himmat site based on Raven Street meets the needs of pupils who have been excluded from mainstream schools in the Halifax area. Pupils who attend are predominantly referred by the Phoenix pupil referral unit. Currently pupils who attend are from Years 9, 10 and 11.
In the damning report it also said: "On the Himmat site, there is a lack of clear and effective leadership. As a result, many systems are not securely in place and pupils’ behaviour is often unregulated and sometimes out of control. Academic progress is poor.
"The roles and responsibilities of staff and leaders are not clearly defined particularly on the Himmat site.
"This leads to confusion and a lack of effective leadership and management structure.
"For example, when the lead inspector asked who was responsible for the day-to-day leadership of the Himmat site, it became clear that there was a lack of clarity around roles and responsibilities."
The Ofsted report also said the recording of safeguarding incidents, including accidents, injuries and pupils’ difficult behaviour, particularly on the Himmat site, is inconsistent and of inadequate quality.
The school, which at the time of the inspection had 31 pupils aged between 11-19, is based on three sites.
The Ummid site, off Great Horton Road, houses the school’s main office and pupils there are from Bradford and have been permanently excluded from mainstream schools.
The Junction site, off Duckworth Lane, is for pupils who have been excluded from mainstream schools and are waiting to start at a new secondary school.
In a statement, the school's board of trustees said they were very disappointed with the Ofsted judgement but fully accept the findings.
The board said it closed the Halifax site immediately following the report and had temporarily closed one of the schools in Bradford.