He is believed to have become angry after some youngsters kept pushing exit buttons in their desperation to get off.
"People were grabbing their phones and calling their parents," a Year 9 Green Bay student told the Herald. "We were really worried when he missed the last stop and just kept driving," she said, adding that the driver reversed the bus only after reaching the Huia Settlers Museum where the road narrows.
"When he finally succeeded the students were panicking."
Although Ritchies managing director Andrew Ritchie defended his driver as "a top operator" and a "really reliable, good decent bloke", the Ministry of Education says it has asked the company to remove him from school bus duties while conducting its own investigation.
Several students used an emergency button to open a door to jump out of the bus as it slowed to cross back over the one-lane Huia bridge after the driver threatened to return them to Green Bay High without letting them off.
The school emailed families saying one had suffered an injury after "a breakdown of communication" with the driver, and assured them it was following up Monday's incident.
Principal Morag Hutchinson told the Herald she was trying to establish all the facts, but was a parent herself and "of course I'm concerned about making sure the kids are getting on the bus safely and arriving safely".
Glen Eden acting principal Mark Whitford said his school was also investigating the incident.
Mr Ritchie denied a student's foot had been run over and said that while he had yet to learn all the facts, "what I have been told is the kid who jumped out might have twisted his ankle, which is his own fault".
He said the students "were misbehaving" and that the driver was taking them back to school, which was "the normal procedure" in such situations.
He also told 3News: "They were stupid bloody kids, what they did was illegal to open that back door while the bus was moving. There were four to five kids causing problems and they were sitting on the buzzer."
Glen Eden pupil Zoe Tibbutt, 11, said the driver "seemed flustered, he kept going in the wrong direction, and almost hit some road signs".
Parau resident Joop Van Herk, whose 15-year-old son "flooded off" the bus with other students at Huia, posted on Facebook that he had told her children were crying "and some of the older ones tried to talk sense into the bus driver".
Mr Ritchie said it was physically impossible to drive a large bus erratically or fast on such winding roads.