His call coincided with the leak of the criteria to be used by the government to determine which schools should be closed, including a recommended minimum of 150 enrolments for primary schools and 300 for secondary and combined schools.

The depth of feeling on the issue saw a protest by up to 100 residents at Ringarooma, where the primary school is on the government's hit-list.

Mr Hall said he had written to Education Minister Nick McKim requesting that he give urgent attention to sparing regional schools that were earmarked for closure.

"It is a matter of grave concern that the state government's list of schools to be closed seems to be predominately and unfairly aimed at regional communities," Mr Hall said.

Access to a local school was an important consideration for people living in regional communities or those considering moving to such areas. He also had concerns about the transition of students affected by school closures.

"Many of the other regional schools are already running at full capacity," Mr Hall said.

Deputy Premier Bryan Green said the government understood the attachment that people had to their schools.

"The formula that's been arrived at is about trying to ensure that there is a better educational outcome for the students; it's not about just making decisions for cost-cutting's sake," he said.

"It's about ensuring that we get education on a sustainable footing going forward and in fact improve educational outcomes.

"It's tough, we know that, but it's something that we just need to work through."

Opposition Leader Will Hodgman said his party was opposed to any forced school closures.

"We will fight every step of the way with communities to keep schools open," he said.

But Mr Hodgman also said a proper analysis was needed before any decision regarding the closure of schools was made.

"And it's got to be made on the basis of what's in the best interests of the community, the students and parents - not fixing a budget black hole," he said.

Each of the 20 schools on the list - which includes Avoca, Bracknell, Westbury, Ringarooma, Mole Creek and Meander primary schools and St Marys District High School, Fingal campus - has four weeks to put together a submission opposing its closure.

A decision regarding which schools will close is expected by the end of August.