Half of Hamilton's eight public high school principals did not return Hamilton News' calls to ask if synthetic cannabis use was a problem among their students.
Principals at Fairfield College, Hamilton's Fraser High School, Hamilton Girls' High and Sacred Heart Girls' College did not respond to phone calls or emails asking to speak about whether students' use of synthetic cannabis was a problem in their schools and if they had developed a policy for dealing with the substance.
Melville High principal Clive Hamill said his school would review its policy on possession and consumption of illegal substances to include "inappropriate and harmful" substances.
He said the issue of synthetic cannabis was brought to the school's attention by a drug and alcohol counsellor from Care NZ who works at the school one day a week.
"She brought it to our attention that there are substances that are technically not illegal but have a significant impact on a few of our students," said Mr Hamill.