The Larne school held an event on September 30 to recognise the important milestone, with pupils also marking the occasion by burying a time capsule filled with messages in the school garden.
We’ve had a look through the archives and turned up these fab photos of events at the school through the years.
Can you spot any familiar faces?
13. Through the years
Cora, Callum, Conor and Roisin pictured at the St Patrick's Day celebrations in St MacNissi's Primary School, 2007. LT12-372-PR Photo: Larne Times-Peter Rippon
14. Through the years
Some St MacNissi's Primary School dancers with Karen McClean from the Co-Op during the Fair Trade Tea Dance, 2010. LT12-312-PR Photo: Peter Rippon
15. Through the years
Linda, Rebecca and Kelsey making binoculars in the St MacNissi's Primary School P1 class, 2010. LT41-311-PR Photo: Peter Rippon
16. Through the years
Staff join in the Pink Day at St MacNissi's Primary School in aid of Cancer Research NI, 2006. LT41-364-PR Photo: Larne Times