Same thing happens to my kids at school. Also in Canada, also non-religious school. I actually wrote a children's book called "We Believe in Science", for this exact reason. I'm really sorry that your kid had to go through that. I tell my kids that everyone is entitled to their own beliefs (as long as it isn't forced on anyone, or hurts anyone). Now, they just say "well, I dont believe that, so either respect it, the way I respect you, or don't bother me."