The NSW government has backflipped on its push for high-rise schools after its first attempt was plagued by cost blow-outs and delays.

Education Minister Rob Stokes said vertical schools were no longer a "preferred" option because they were complicated to build, less adaptable to students' changing needs and expensive to operate.

Construction at the site of the Arthur Phillip High School in Paramatta. Credit:James Alcock

"There was a lot of initial excitement about the concept of vertical schools," he said. "My ardour is not as strong in relation to them."

The first high-rise school, Arthur Phillip High at Parramatta, was supposed to open this coming term but has been delayed until at least term four after a problem-plagued construction. The cost, which includes neighbouring Parramatta Public School were originally estimated to cost $100 million, but has blown out to $325 million.