The new building cost $2.3 million and will be used as a multi-purpose room for testing, functions, sporting events and assembly.

Afternoon tea in the new building will start at 2.30pm, following a speech from historian and author Ross McMullin. 

Old Collegians Jan Clarke, Margaret Cochran and Jack Netherway will attend the event, sharing stories from their time at the college. 

During their schooling, Mr Netherway was a rower while the women played tennis, hockey, basketball and baseball. 

“Girls weren’t allowed to row in those days,” Ms Cochran said.

Mr Netherway, who graduated in 1941, has spent most of his life working with the school.

“There were only 109 kids when I left the school,” said Mr Netherway, a former vice principal.

Now boasting more than 1300 students, the school is Victoria’s fifth oldest private school.

“It’s fascinating to see the development of the school’s buildings, numbers and facilities,” said Ms Clarke, who finished her schooling in 1948. 

Before PLC and Ballarat College joined in 1974, the girls would ride their bicycles to the boy’s school for math and science classes. 

Ms Cochran, from class of 1949, said the merger was due to a post-World War II shortage of teachers and education facilities. 

“It was basically an economic thing,” Ms Cochran said.

The alumni was only taught in one classroom, leaving them dumbfounded as to the development and transformations of the school.

“I’m just amazed as to the size of everything,” Ms Clarke said.

“I feel very proud that the school has been contributing to Ballarat for over 150 years.”

The past students are excited to open the new centre as they often return to the school for functions and student reunions. 

In regards to the next 50 years, Ms Clarke said: “I hope we’ll still be educating people broadly and well.”