Some parents are furious after learning their children were tricked by school leaders into chewing moose droppings on a class canoe trip in Manitoba.

Karen Eyolfson, whose 13-year-old son was one of two students to bite into the droppings, has pulled her boy from Walter Whyte School, saying the trust between staff and students has been broken.

It happened during a school trip on May 25. Two Grade 8 teens from the school in Grand Marais, Man., were given the poop but told they were chocolate-covered almonds.

Three staff members have been disciplined for not stepping in to stop the joke played on the students with moose droppings. (infonavigate.com)

"He dug into a bag and popped one in his mouth. As soon as it hit his mouth somebody tells him, 'You just ate moose shit' and the whole group of people started laughing at him," said Eyolfson.

She said it was a parent chaperone that offered her son the so-called almonds from a sandwich baggie. But the principal of the school, a resource officer and her son's teacher all watched it happen, Eyolfson said.

"Who is he going to go talk to? The counsellor was in on the joke and so was the principal. They were the bullies, so who would he talk to in hopes that something would be done?" she said.

Droppings stuck in girl's braces

When her son ran off to wash out his mouth, a 13-year-old female classmate who didn't witness the incident was also tricked by the same adults into eating the droppings, Eyolfson said.

The girl got it stuck in her braces and was humiliated, said Eyolfson.

Even though it was a parent who played the joke, the staff members are still responsible, said Lord Selkirk School Division superintendent Scott Kwasnitza.

"There's certainly an expectation that they will protect our children and this, this didn't need to go as far as it did. And the staff should have intervened in a timely fashion," he said.

Kwasnitza said three staff members have been disciplined, but he wouldn't reveal the nature of the action taken against them.

Eyolfson said she and other parents want the principal transferred but that has not happened.

Not a joke, anti-bullying expert says

An international anti-bullying expert is shocked by the incident.

Rosalind Wiseman, a Washington-based author on bullying, said anyone who believes the parents are overreacting is wrong.

"You have braces on your teeth and you cannot get excrement out of your teeth because of what your principal did to you. I mean, that is not a practical joke," she said.

Wiseman said the school division should order the staff involved in the incident to take anti-bullying training, as well as provide more information to the shaken parents.

"This is about adults needing to be clear of [what] their … basic roles and responsiblities are, and that they not only failed, but that they colluded with each other, to humiliate a kid," she said.

"Honestly, if those adults don't apologize to those children, they have failed again."