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?
1. Through the years
St MacNissi's Primary School held a variety of charity fundraising events in 2007, including bring and buy sales, book fairs and bun sales. Pictured are some of the children and principal Mrs Brady handing over a cheque for £1000 to Sister Mary McAteer for a mission in South Africa. LT26-359-PR Photo: Peter Rippon
2. Through the years
Performing the Haka at the St MacNissi's Primary School Fair Trade Tea Dance, 2010. LT12-310-PR Photo: Peter Rippon
3. Through the years
Daniella, Eva, Erin and Cara at the St MacNissi's Primary School Halloween Parade in 2010. LT44-349-PR Photo: Peter Rippon
4. Through the years
Winners of the Port of Larne Christmas tree decoration competition from Cairncastle and St MacNissi's Primary Schools, pictured in 2006 with Harbourmaster Trevor Wright, P&O Irish Sea customer manager Laura Gilmour and Stena Line operations manager Shane Forsythe. The winners are (from left): Matthew (3rd), Nicole (1st), Eve (2nd), Declan (3rd), Shannon (2nd) and Sarah (1st). LT51-328-PR Photo: Larne Times-Peter Rippon