Disabled children are being put at risk after chaperones were removed from school buses, parents said.
Some pupils who used the free council bus service with guides to the Wilson Stuart School in Birmingham were told they did not need it.
Parent Heidi Wells said her 15-year-old disabled son could choke on his saliva without a chaperone on the bus.
Birmingham City Council said it prioritised children with the greatest need for a guide.
About 24 of the school’s pupils, on three bus routes, were told in a letter about the changes three days before the Erdington school, which caters for pupils with physical disabilities and complex medical needs, started in September, Mrs Wells said.
Her son Jack has cerebral palsy, and condition dysphagia, which causes him to choke on his own saliva.
She said without the guide he had last year to keep an eye on him during his journey to and from school, he could be in danger.
“The council have cut it because of cost,” she said.
“I have had no explanation.”
She added her son was now regularly late to school because she needed to drive Jack herself – as well as dropping his siblings off at other schools – because it was too dangerous to catch an unguided bus.
Tanya Cleaver said her five-year-old daughter with cerebral palsy and chronic lung disease was also denied a guide on the bus, despite having one previously. The council said she would now get a guide on the bus from Friday.
Ms Cleaver said: “It is all right saying ‘if there’s an emergency the driver will pull over and stop’, but that will be too late for children like Nadine or Jack.”
Wilson Stuart executive head teacher Steve Hughes said the council had not consulted them about removing guides from some pupils.
School governor and Conservative shadow cabinet member for children’s wellbeing, Councillor Alex Yip, said: “We want to know, have they done risk assessments for the children, and why was there four days’ notice and no consultation?”
In September special education needs provision for pupils and young people across Birmingham was described as “weak” by Ofsted.
A Birmingham City Council spokeswoman said it had responded to all concerns raised.
It said annually reviewed travel routes pupils who qualify for assistance and, where necessary independent ,occupational therapy assessments are undertaken.
She said: “We have a finite number of guides and will always prioritise routes where the children have complex care needs that require the support of a guide.”