Cannabis has been legal in Canada for nearly six months, but educators and parents still have plenty of questions about how to talk about toking with teens.

It's a topic that Dr. Muffy Greenaway, a child and adolescent psychiatrist, deals with all the time in her practice. Since legalization of marijuana last October, she's noticed a difference in the kinds of conversations surfacing.

"There is much more open discussion about cannabis both from the kids and the parents," said Greenaway, who's also a clinical instructor for the Department of Psychiatry at the University of British Columbia..

"I've also noticed that kids are using much more."

Greenaway took part in a panel event hosted by UBC's Faculty of Education in Vancouver last week that focused on teaching young people about responsible cannabis use. She spoke to CBC about her observations.

"It's going to be a different conversation with a 22-year-old versus a 13- or 14-year-old," said Greenaway, who works with both age groups.

Ferrari versus Camry 

One of the questions that comes up often, she said, is around the risks of using marijuana as a teen because of the amount of propaganda on both sides of the debate.  

"What we know is during the teenage years, the brain is developing and undergoing renovation," she said.

"Daily use of cannabis floods the receptors in the brain that then alter the neurons."

And that can have all sorts of implications for attention, memory, perception and executive functioning.

"The adult brain that should be functioning like a Ferrari ends up functioning like a Camry — no insult to any Camry drivers out there," she said.

It's not always easy to deter cannabis use simply by pushing the danger message.

"You have to respect that they're going to make their own choices," she said.

"The conversations really should be like having a conversation about alcohol: what does it do to your body, how are you going to stay safe?"

And for parents who smoke themselves? Not everyone wants to admit it to their kids.

"I've certainly seen parents who have been very open about it and others who hide," she said

"It's going to be a personal decision that people have to make within their family culture."