According to freedom of information documents, there are 215 portable classrooms being used in the municipality, 72per cent of them older than 20 years.

The Liberal Party claims the oldest is a Bayswater West Primary School classroom that is 45.5years old. At Rowville Secondary College, there is a classroom that is 43.5 years old and two that are 42.5 years old.

Shadow Education Minister Martin Dixon said portable classrooms were meant to be a "short-term solution".

"Any parent would be appalled and shocked to learn of the high number of old portable classrooms in use across Victoria.

"The Brumby Government needs to stop all the self-promotion and allow our children to shine in modern classrooms, instead of in ancient deteriorating portables."

Education Minister Bronwyn Pike, however, labelled the Opposition as "hypocrites" who were "vigorously opposing spending on new schools in communities across Victoria".

"In government, the Liberals and Nationals sacked 9000 teachers [and] closed 300 schools. And they have continued to attack the education system from outside Government, opposing...record investment in school building."

Bayswater West Primary School and Bayswater Secondary College declined to comment on the matter.

Meanwhile, Liberal MP Nick Wakeling has continued to attack the State Government for the high cost of maintaining the vacant Ferntree Gully Primary School and Ferntree Gully Secondary School sites.

In a response to a request from Mr Wakeling, Education Minister Bronwyn Pike confirmed that more than $500,000 had been spent on building maintenance and upkeep of the grounds.

The Government plans to use the primary school site for a social housing development.