At the Baulkham Hills North Public School in Sydney’s outer west, space is so tight teachers are forced to stand in the staff room and the students have to take turns using outdoor areas.

There are almost 900 children crammed into the school, almost double its intended student population. Half the classrooms are demountables, which former parents and citizens association president Alison Mackey says leak during bad weather, are prone to mould and have further shrunk the space otherwise available to the kids.