Does Canada have some sort of constitutional or legal restriction on teaching or practicing religion in the public schools?
Dizredux
I'll jump in and try to answer this:
Technically, Canada is a Christian nation. Our Charter begins with the line, "Whereas Canada is founded upon principles that recognize the supremacy of God and the rule of law..." Our head of state is also the Queen of England, who is the head of the Anglican Church.
However, one of our freedoms, found in that same Charter, is a "freedom of conscience and religion," and this has been interpreted that the government should not overly favour one religion over another. It still does - as was mentioned, Catholic schools get public funding in Ontario - but the population is now so diverse and secular that I doubt that any government could go very far attempting to advance a single religion.
Sometimes governments still attempt it- go look up Quebec's Charter of Secular Values from last year - and can do so by an oddity in our charter: the Notwithstanding Clause, which allows a government to override the Charter if they deem it necessary. It's rarely used and is heavily frowned upon, but I do know the previous Quebec government was intent on using it to pass their odious charter. I've found, though, living here basically my entire life, that governments and the populace at large leave religions alone so long as religions don't try to interfere with anything else.
Also, another comment: I went to those private Christian schools in Ontario, and I can tell you that in highschool biology, students are taught the ToE. It isn't stressed, but it also isn't downplayed or denigrated, and YEC is not taught at all outside of the Biblical studies courses. Of course, I can only speak for the schools my cousins and I went to, but those were the two largest in the country. I would imagine that in some of the farther reaches there may be issues, but not in the big urban schools.
EDIT:
My 6th grade science teacher was the brother of a Baptist preacher and a devout Christian himself. We covered the Creation version in one class as a debate. I drew the lucky straw and represented the Creation side and won the debate, but my opponent was ill prepared so it was too easy.
I also had this debate, in my Grade 10 Biblical studies course. I had to defend naturalistic evolution, the position that very few people in the class knew much about and even fewer actually accepted. I was still able to win the debate, mostly through being able to out-logic the arguments more than any real evidence.