Teachers and principals are relying on other students to know if someone is bringing a weapon to school.
Figures released under the Official Information Act show 526 students were stood down, suspended, or excluded for using or having a weapon at school last year.
That's 80% higher than in 2018.
PPTA President Chris Abercrombie told Ryan Bridge the experience of most schools tends to be the same.
He says bag searches are very rare, and more often than not, students tell staff about the weapon.
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