Changing templates by mistake when using Canvas?

I am a fairly new user of Kami and have it integrated into my Canvas classes. My problem is using it as a teacher. After I have created a Kami assignment in Canvas for my students, I will open up the assignment in Canvas and Kami during class. As I write on the assignment, I want students to take notes on their copies and then solve more problems. However, my notes end up on their copies. I believe the problem is that when I open the assignment on Canvas, I am working directly on the template and not a local instantiation. Is that the case? Is there an easy way to avoid this, or should I just not open Kami files using Canvas in class?