"There will be as many adults as students in the classroom," he said.
After the morning tea, Peter Scott, a member of the original staff, officially opened their revamped Conservation Area. "He was a big part of planting all the trees in the Conservation area in 1968 to 1970," Mr Popping said.
Today, the school would also host what it was calling "A Walk Down Memory Lane", where guests would be guided to see the school memorabilia presented all over the school hall.
The only other surviving past principal, Ian Farquhar who led the school from 1990 to 2000, is also expected to be attending the celebration.
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Mr Popping said although the school still had the original buildings, it had come a long way from a 1960s look to a modern school using technology.
"It's built of all the initiatives of the past," he said.
However, he was not sure the pupils were different from the previous years.
"I don't think the children have changed much," Mr Popping said. "They're just as excited and curious and certainly bring a lot of skills and talent to the school."
Student Daniel Penhey, 12, was excited about the day. "Grandma is going to come and spend time in class with me." He intended to show her his school work, and his 3D artwork.
Afterwards, his grandmother, Beth Watson, said the event was "lovely, most interesting".