Northampton office blocks 'to be used as schools'
An "unprecedented" rise in school age children numbers in Northamptonshire has prompted education bosses to consider office buildings for teaching.
The county council expects its secondary age population to rise by 9,369 by 2024.
As well as building new schools, the authority says it would consider using commercial premises when suitable.
The National Union of Teachers (NUT) said it was concerned whether such buildings would be "fit for purpose".
The council is currently involved in a scheme to turn the former post office sorting office in Northampton into a 2,200-student "learning environment" for children aged between four and 19 years old.
And Abington Vale Primary is using a former office block - 1.5 miles (2.4km) away - as a secondary "campus".
A council spokesman said the authority would always prefer to extend existing, or create new purpose-built, schools, but using suitable commercial buildings would be considered.
Matt Golby, cabinet member for learning skills and education, said: "We have got to provide about 30 new schools and at the current rate [demand is rising by the equivalent of] a new two-form primary school every couple of months.
"Northamptonshire has unprecedented growth in pupil numbers through a combination of birth-rate increases, inward migration and house building."
A spokesman for the Northamptonshire branch of the NUT said: "Our main concern would be whether such buildings were fit for purpose.
"There are a wide range and age of commercial buildings and our view is that schools have unique needs which demand they should preferably be purpose built with all appropriate indoor and outdoor spaces sufficiently designed for young people."
The spokesman added the branch was "relatively satisfied" the county council's approach to commercial buildings as potential school sites was "careful" in its approach.