Students at an Adelaide high school have been issued an assignment to find research disputing the health dangers of marijuana use.

A Salisbury High School Year 9 maths class was divided into two, with one half asked to research statistics disputing the dangers of smoking marijuana, while the other looked into the dangers, The Advertiser reports .

Teacher Greg Perkins reportedly now regrets the way he issued the project, saying he should have asked each of them to talk about both sides rather than organise a debate.

He told The Advertiser he was inspired by a study in a medical journal that found teenagers who smoked marijuana were seven times more likely to commit suicide and eight times more likely to use other drugs later in their lives.

He said there had also been studies showing that smoking marijuana did not increase the likelihood of users showing signs of schizophrenia.

“I instructed them to look at reliable services…. I haven’t been saying get on some random internet site that has no scientific basis and start grabbing information from there,” Mr Perkins said.

He said Salisbury was a “rough area” and it would not be the first time the students had heard about marijuana and it was likely some of their parents were users.