A hidden mural that could be more than a century old has been discovered at a primary school in Melbourne's inner east.

Key points: Images on the chalkboard include the Australian coat of arms, native birds, an elephant, the Union Jack and a girl holding flowers

Images on the chalkboard include the Australian coat of arms, native birds, an elephant, the Union Jack and a girl holding flowers Kew Primary School is celebrating its 150th anniversary this year

Kew Primary School is celebrating its 150th anniversary this year The building the drawings were found in were constructed in 1910

The chalk drawings were found over the Easter break during renovations at Kew Primary School's prep building.

"First, we saw a splash of yellow," principal Peter deWacht said.

"Then a couple of animals, holding up the crest, the Australian crest, and it felt as though we'd danced back into time."

The 9-metre-long blackboard with the drawings was hidden behind newer blackboards and storage cupboards.

Parts of it have faded, but images in red, yellow and green remain vibrant.

The mural was found on a chalkboard in a classroom built more than 100 years ago. ( ABC News: Iskhandar Razak )

The Australian coat of arms is the largest mural, but it isn't alone.

Native birds, an elephant, the Union Jack, and a girl holding flowers cover the blackboard.

The word "ARCTIC" and some arithmetic are also visible.

'A gift from the past'

The school is celebrating its 150th anniversary this year and the renovations were started to mark the occasion.

The building the drawings were found in was constructed in 1910, leading to speculation the work could be a century old.

"What we found was a gift from the past," said Mr deWacht, who has only been principal there for just over a year.

Some of the drawings, including a girl holding flowers, are still vibrant. ( ABC News: Iskhandar Razak )

The school's business manager, Carmel Buxton, was on site when renovators found the chalk mural and she believes it was hidden on purpose.

"I saw yellow flowers, and a girl holding the bouquet, and then we just kept pulling and pulling and pulling. It was fabulous," she told the ABC.

"They decided to leave us a present so that one day the right people would come to the school as custodians."

However, she thinks the school's smallest students may not be as thrilled as she is.

"The preppies will just think it is really pretty in their space, which it is, but it is also pretty exciting."

It's not the first-time old chalk drawings have been discovered hidden at a school.

Last year, nursery rhyme images were found by builders on a blackboard at Northcote Primary School which were drawn by a former teacher in 1959.

Finding the mystery artist

Kew Primary School will now embark on a quest to discover who was responsible for the newly revealed drawings.

Principal Peter deWacht is planning to get the whole school involved in a quest to discover the artist responsible for the mural. ( ABC News: Iskhandar Razak )

Mr deWacht said he thinks it could be a long-term project, not just for the administration team, but the entire student body, once students are allowed back on site.

"We will have students working with artists to restore the mural but also adding their touches to it," he said.

"It's such an amazing thing. The school was started in 1870 so we have had generation after generation growing up and learning in these halls.

"We feel the weight of history and that we are responsible for it and we want to make sure that we are handing it onto the future in pristine form."