Schools in the eastern suburbs of Christchurch face a drop in enrolments, and staff cuts, as thousands of residents leave their quake-damaged homes.
February's earthquake has already has an impact on school rolls, with some cut by up to 40%.
But the news that more than 5000 residents have to abandon their homes means many schools face an uncertain future.
Burwood School principal Doug Watkinson says 50% of its students are living in red-zoned properties.
And Avondale School, which is already down 150 students since last year, is set to lose a further 20 pupils.
The Ministry of Education has contacted all affected schools and will meet them to discuss the impact of falling rolls next week.