A bus taking children to Thorner’s School in Litton Cheney is causing traffic chaos, wasting staff time and endangering children, say staff and parents.
The 46-seater vehicle is too big to get up the lane to the school so blocks the village road twice a day as the children get on and off, they claim.
It also means two members of staff have to escort the children morning and afternoon.
Headteacher Jyotsna Chaffey said the bus was supposed to be a temporary solution while the bus company Damory found the right size bus with seatbelts for 30 children.
It used to send a smaller one but not all the seats had belts.
Parent governor Kim Pearse said this put staff in an impossible situation.
She said: “Which child do you decide not to put the seat belt on? As a teacher you can’t make that decision. What if something did happen? Whose responsibility is that?”
Although there is no legal or contractual requirement for the buses to be fitted with seatbelts parents decided they were not prepared to use a bus without them.
A four-year-old child has already been hurt falling out of the seat, said Mrs Chaffey.
She has also had to take a child off the bus and call parents to collect the pupil. Both the school and parents complained to Dorset County Council.
Mrs Chaffey said the school had a series of meetings with the bus company to resolve the problems.
The company asked if the school would be happy to have a bigger bus.
Mrs Chaffey said: “I said yes because I assumed it was going to be temporary but this has been going on since January and they don’t seem to be showing any signs of getting the appropriate size bus.
“The bus blocks the lane, obviously it’s chaos. Anyone not on the bus comes in a car so there are parents piling up at the bottom of the lane trying to get in.
“It is just madness down there at the start and the end of the school day and so unnecessary.”
Mrs Pearse added: “It affects the children’s safety and learning time. And since January we have had five or six different drivers on this route that is quite perturbing.
“One of the drivers took the wrong way home which was quite upsetting for the children.”
Litton Cheney Parish Council John Firrill said the council fully supported the school’s bid to resolve the issue.
A spokesman for Dorset County Council said it was working with Damory to try and resolve the situation.