The non-government sector, set to be hit hardest by the changes, has also questioned the data and consultation behind the design of the new system, which will dump most dedicated school buses in favour of more public services running past schools when it comes online in January.

A spokesman said Transport Canberra was taking on board community concerns about safety but the improved network would make better use of its fleet and keep transport sustainable for a growing city, as a number of school services were currently under-utilised.

Ideas such as moving public bus stops closer to schools and installing more pedestrian crossings were being worked through as the government met with school communities.

But, following a meeting between school leaders and Transport Canberra on Tuesday, a number of principals, including at Brindabella Christian College, St Mary MacKillop and Good Shepherd Primary, said very little consultation was taking place on what now seemed like "a done deal" .

While the government spokesman said faster services would make travel easier for students, some principals have warned the changes could compromise the ACT's vision for a more sustainable city by putting more cars on the road as children face longer walks to bus stops and frequent changes at busy stations.

Laura and Matthew Sham say they will be giving up their morning walks to the bus stop with their young sons in favour of long car rides to Brindabella across town.

The family had chosen to send their sons, Noah, 10, and Elijah, 7, to the school because there were dedicated school services available. All 17 of those services will be cut in the new system, though two routes will ferry students directly from interchanges.

"I'm not putting them on a public bus, they're too young to navigate an interchange like Woden by themselves," Ms Sham said.

Transport Canberra said MyWay data indicated more than half of students catching buses in the territory already used the public network. Of the 49 primary schools set to lose all their dedicated buses in the change, an average of eight students were on board each bus in the morning, the spokesman said.

But opposition spokeswoman for transport Candice Birch said families had long been calling for more dedicated services not less and a number of non-government schools reported their afternoon buses were almost always full or close to full.

At large schools such as St Mary MacKillop and Marist College, principals estimated up to 11,000 students were piling onto buses after the bell each day.

Marist deputy headmaster Ryan Greer said the school even started running its own private buses in 2015 to meet demand from growing enrolments in the north. While he acknowledged the need for a sustainable bus network, Mr Greer said student safety should not be compromised as a result.

"In other cities like Sydney they might have kids on public transport, but they also have the culture and infrastructure around that already, rather than just changing it all in one go," he said.

At Good Shepherd Primary, principal David Austin has just come in from bus duty. His school has a much smaller percentage of kids catching buses compared to K-12 campuses and will lose all its dedicated services in the change, but he said he regularly helped students as young as kindergarten age onto the bus.

"Parents have peace of mind with a school bus, the kids know the driver, it goes direct, we supervise them getting on," Mr Austin said.

"I really think this will affect enrolments and parent choice in the future."

Ross Fox at the ACT Catholic Education Office described the changes as a significant concern as non-government schools tended to have more kids travelling from outside their local area and younger students catching buses.

"It seems as if non-government schools haven't been considered at all in this," he said.

In the public sector, Janelle Kennard of the peak association for parents' groups said families also had a strong preference for dedicated services and direct buses which did not go through interchanges.

But the association had been working closely with Transport Canberra this week to discuss problems in the proposed network and were hopeful more direct routes could be included for students attending their local high school, she said.

"There's about eight high schools we're concerned about in particular, where kids will be taken out of their way back to an interchange, or some kids if they live in the wrong place there's no bus."

A spokesman for Transport Canberra could not confirm if the government would follow through with creating direct services for public high schools but said feedback was being taken seriously.

While some schools has slammed the changes as an exercise in cost-cutting by the ACT government as it prepares to bring light rail online, Transport Canberra said operating costs on the new bus network were actually due to go up, not down.

Public consultation on the plan ends on Sunday. Visit yoursay.act.gov.au/rapid-bus-network