Associate Education Minister Nikki Kaye said the new contract with the consortium Interlink would be "invaluable" in situations where a new building was needed as soon as possible.
The portable classrooms would be high-quality and match the same standards as modern, permanent structures, she said.
"The new transportables are modular, which means they can be put together in a number of different ways to create whatever learning space is needed - everything from a single or double storey classroom to a dance and drama studio.
"Current estimates are that it will take just four to six months from when an order is confirmed to installation on-site. Previously, it could take at least eight months to complete this process."
The transportable buildings were able to be transferred between schools many times, Ms Kaye said.
The contract is worth more than $100 million over 10 years and the classrooms will be built in factories in Auckland and Christchurch.