My mother was born in what was East Germany, she came to Canada at the age of ten as a refugee, she is now a Canadian Citizen and was when I was born in Calgary, AB Canada in 1974. Both my grandparents were also German but became Canadian. Do I qualify for a german passport, or a dual citizenship.

First, I do not see a reason for you to qualify for dual citizenship.

Unless your mother was part of a diplomatic mission or some form of German ambassador to Canada, then you would have the citizenship of the country you were born in.

That said, if you wanted to become a German Citizen, then contact the German Consulate in Canada and see what you have to do to renounce your citizenship.

Dual citizenship expires when you turn 18, I believe.