The number of pupils expelled from school is at its highest for 10 years. More than a third of the cases are due to drugs.
Ministry of Education figures show drugs accounted for 71 of the 209 expulsions last year.
Only students aged 16 and over can be expelled.
Some educators are blaming the 209 expulsions last year on a lack of jobs keeping disinterested pupils in school for longer.
Details obtained by Radio New Zealand News under the Official Information Act show there has been a 40% increase in the number of expulsions per 1000 pupils, in the past six years.
The Ministry of Education says there is no clear pattern of increasing expulsions, as there are yearly fluctuations in both expulsions and school population.
But data shows they have gone up every year since 2004, apart from 2008 when there was a slight dip.
Spotswood College in New Plymouth last year had eight expulsions - the most in the country.
Principal Mark Bowden says most of the pupils at the decile 5 school were expelled for repeatedly smoking cannabis.
He says those advocating cannabis decriminalisation must be aware of the impact of their messages.
Drug exclusions also rising
The Principals Federation says an increase in exclusions for drugs is becoming more common.
An exclusion is when a pupil under the age of 15 years is excluded from their current school and placed in another.
Last year drug exclusions accounted for 290 out of an overall total of 1412 exclusions.
Last year drug exclusions accounted for 290 out of an overall total of 1412 exclusions.
Principals' Federation president Peter Simpson says the increase is no surprise.
The rate of drug expulsions increased from 2.17 per 10,000 pupils in 2006 to 6.96 last year.
Continual disobedience was the next cause for explusions with 47, followed by physical assault on other students, with 27.
The rate of exclusions for drugs also jumped from 3.38 in 2006 to 4.65 in 2010.
