Addington Te Kura Taumatua Principal Donna Bilas said the bell has played a significant role in the school’s traditions since it was founded in 1881. It was discovered missing on Monday.
Bilas told RNZ: "The kids all enjoy having their opportunity to ring it to start the day, but it is also a huge part of celebrations and commemorations that we hold here at school."
The school is appealing to the local community in the hope of retrieving the bell.
"If anyone has seen it, seen someone with it, we just want it back.
"It's our heart, it's our history. We won't ask any questions.
"If you find it, please, please bring it back."
The bell is "about the size of a basketball and very heavy", with Bilas saying that she thought it was made of brass.
The school believed the bell was taken to sell for metal.
"Other schools locally have had brass and copper taken before.
"To actually take the time to come in in the weekend and take this off our tamariki is hugely upsetting."
Bilas told chrislynchmedia.com: “When we went to ring the bell every morning like we do, it just wasn’t there. It had been ground off with a power tool. It’s like a part of us is missing.
“The bell is a feature of many school traditions,” Bilas told Chris Lynch Media.
“At the end of each year, we gather for every child or staff member who is leaving to ring the bell - rain or shine.
“The kids then shake hands with all staff and our haka is performed. In its new space, it has steps for students to climb to it if they are short and also for a wheelchair to pull up to.”
The remembrance garden, where the bell was located, also holds a plaque commemorating the 51 shuhada who lost their lives in the mosque shooting, including a past parent.
Each year on March 15, the school community gathers to remember them, with the bell ringing as part of the ceremony. The garden also features a tree planted in honour of the King’s coronation.
“We know it was taken after 4.15pm Sunday as it was heard being rung when a teacher who had just finished working on site was leaving,” Bilas told Chris Lynch Media.
“We just want it back, no questions asked. Just give us our heart and history back.”
The school is urging anyone with information about the bell and its whereabouts to come forward.
