School 'failed to provide soap, toilet roll or drinking water' for pupils
Pupils had to ask staff for toilet roll each time they needed to visit the lavatory, school inspectors found.
An Ofsted team also discovered that it was "common practice" at Park Avenue Girls' School in Stoke-on-Trent, Staffordshire, not to provide soap for hand-washing "or suitable drinking water".
The Muslim independent school was rated inadequate in a formal report which also found pupil safeguarding to be "ineffective" and education outcomes below standard.
Following a visit carried out in October, Ofsted found that: "At the time of the inspection, it was not the school's common practice to provide soap for pupils' hand-washing, toilet roll in the toilets or suitable drinking water.
"Toilet paper is available from the school office when pupils request it.
"Pupils told inspectors that they sometimes avoided using toilets for the whole school day because of this."
The report continued: "During the inspection, leaders began to put toilet roll into the toilets, provide soap and suitable drinking water."
Too many pupils, of whom there are 34 on the roll, "attain below their capabilities", particularly the most able.
The school had developed systems to be able to monitor pupils' development and progress, but these were "not yet having a strong impact".
Inspectors, who published their report at the end of November, also "found published sectarian material in a storeroom behind the school office".
The headteacher, who was unaware of the literature, "confirmed that he planned to destroy the material".
Ofsted "did not find any evidence that this sectarian material had influenced teaching or learning in school".
The report also found that pupils were "well-prepared for life in modern Britain" and the school did "promote fundamental British values in their lessons".
It added: "Pupils study a range of world religions. Inspectors observed them discussing these in detail, with sensitivity, understanding and respect, thereby acquiring an effective understanding of why different people's faiths are important to them."