Official reports on public school playgrounds reveal weapons such as knives, tomahawks and replica guns are being found on a regular basis.
The statistics come from serious incident reports filed by NSW public schools between April last year and March this year.
Documents show knives were found on students on 57 occasions last year, while four students were in possession of tomahawks.
There were three hospital admissions for stabbing injuries in separate incidents, while at least 11 replica pistols were found and other home-made devices such as pens with pencil sharpener blades attached to them.
The disturbing documents come as five teenagers are expected to be sentenced today for a rampage on Merrylands High school in April involving machetes and samurai swords.