NSW will need an extra 386 primary school classrooms every year for the next decade to cope with booming enrolments, and more students will be forced back to the public system because Catholic and private schools will run out of room, a new report warns.

The Australian Council for Educational Research (ACER) report says as the population of primary students increases dramatically over the next 10 years, schools will need significantly more classrooms and resources and new schools will need to be built in "outer metropolitan growth corridors".

Strain on the system: The number of children in primary schools is set to rise by more than 92,000, ACER report says.

Between 2001 and 2010, the number of children in NSW primary schools fell by about 9000 but from 2011-2020 the population will rise by more than 92,000 students, the report says.

Secondary schools will not feel the impact until 2018 but growing student numbers in high schools will also mean a greater demand for teachers, especially in physics, IT, mathematics and chemistry. More teachers opting to work part-time and male teachers retiring will add pressure, the report says.