The group SEND Action wants to know why the inspectorate has appeared to make seemingly conflicting comments around the practice at two different schools.
The regulator downgraded Holte School, in Birmingham, from “outstanding” to “requires improvement” after discovering in October that Year 11 pupils at alternative provisions had been removed from the school roll.
According to Ofsted, Holte School is not following “government advice about how pupils who study away from the school, at alternative provision, should be registered”.
It adds: “Leaders could not give inspectors a clear reason why they remove these pupils from the school roll in Year 11. There is no evidence that this practice benefits the pupils. It means that information the government publishes about the school is not accurate.
“Ofsted refers to this practice as ‘off-rolling’. It should not happen.”
But the regulator declined to call the same practice – involving alternative provision educated pupils – "off rolling" when it was discovered last month at Inspiration Trust-run East Point Academy in Lowestoft.
Ofsted said: “Leaders could not show how this was in pupils’ best interest,” adding that “these processes are not exacting enough”.
The inspectorate notes that the school no longer removes those who had attended alternative provision when they reached Year 11 and “the few pupils previously taken off roll have since been reinstated”.
SEND Action asked Ofsted “why these practices are identified in one school as off-rolling and not in the other?”
It adds: “Who is responsible for scrutinising the inspectors?”
Young people with a special educational needs or disability (SEND) are among pupils affected by off-rolling, which can also include schools persuading parents to take children out of school and home educate them instead.
National Education Union assistant general secretary Nansi Ellis wants to see consistency when off-rolling is suspected.
"We’ll only stop the off-rolling of students if we are honest about the causes,” she said. “Breaking the system up and creating academies has made it much harder to get a level playing field. This is yet another example of Ofsted inconsistency in making judgements about schools.
“We must move to an inspection system that generates support not labels. Many of the students being off-rolled have SEND, and the national SEND funding crisis must be immediately addressed by an incoming government.”
An Ofsted spokesman said: “Our findings about this school are clearly set out in the published letter, and we’ve nothing further to add.”
A spokesperson for Inspiration Trust said: “In its East Point inspection Ofsted made explicitly clear that there is no evidence of off-rolling, and that Inspiration Trust intervened to improve administrative processes around the student roll.
“We were aware that some administrative processes around families who opt to home educate their children needed to tighten up and we have already taken action to address this, which Ofsted recognised. As a result, the proportion of families choosing Elective Home Education at East Point and across the Trust’s schools is reducing.
“Administrative processes have been improved to ensure that when students are being educated in alternative provision, they continue to be registered on our school rolls as well as at the site where they are being educated day-to-day.
“Ofsted recognised the importance that the Trust already placed on inclusion but we have nonetheless gone above and beyond its recommendations to ensure that this important issue is front and centre of our agenda. We have put in place a new inclusion strategy, including a clear programme of staff training and recently held a trust-wide inclusion conference.
“We will continue to provide support and challenge to our schools to ensure that we all have the very best practice across the Trust and meet our ambition of excellence in inclusion.”
Holte School has been contacted for comment.
In September, Ofsted revealed that the number of schools suspected of off-rolling has risen by 13 per cent in a year. The regulator found “exceptional pupil movements” at 340 schools.
A report by the Education Policy Institute published in October found that as many as one in 10 children have experienced “unexplained exits” from their school. Multi-academy trusts have the highest rate of such exits, the report found.
A spokesman for SEND Action said: “We are concerned that Ofsted’s stance on 'off-rolling’ does not appear to be consistent between schools. Regulations are there to protect children and it is vital that exclusions are used in a way that is consistent with the law.
“We are seeing more and more disabled children ejected from mainstream education, with thousands denied their right to any education at all. Where concerns have been raised about unlawful exclusion and a school has unusually high levels of movement, we believe Ofsted should conduct a full and thorough investigation, including interviewing the families of all children who have left the school roll, whether through entering specialist or alternative provision, home education, managed moves or disappearing from education altogether.
“It is not enough to speak to ‘a few parents by telephone’. In one of the reports Ofsted criticises school leaders for their ‘flimsy’ interrogation of why parents were opting for elective home education, but their report is equally flimsy.”