RCMP Cpl. Richard De Jong says two Grade 10 students were dizzy, had heart palpitations and vomited, and one of them had to be taken to hospital after eating dessert squares that contained pot.
"More than two students took the product but only two got sick enough to either leave school or go to the hospital," he said.
De Jong said police believe the Krispy squares and brownies were bought at a 4-20 event, an annual celebration of cannabis culture held on April 20.
"They were selling them on school property, through word of mouth," he said. "The allure of these marijuana edibles, which taste and look like simple sweets, makes them especially risky."
Mounties issued photos of the brownies wrapped in foil and the Krispy squares wrapped in plastic affixed with a label listing the ingredients of cereal, marshmallow, vanilla and canna butter, which is made by boiling butter and marijuana.
"There's certainly no quality control and drugs in general are not guaranteed to be what they should be."
Police are working with school staff to educate students and parents to ensure such products don't end up at school, De Jong said.
"Think of the negative consequences of taking something when you don't know where it's been, how it's made or how you will respond to it."