canadian with student visa in Beijing

Heather, which specific type do you have S1 or S2?
If you have a S2, it may be hard to change it to a Tourist L in Beijing. But it is suggested to go to the local Exit-Entry Adminstration Bureau for asking directly or you can find a local agency to help you to do it.

If you have a S1, you can just change your S1 to a resident permit. With it, you can stay in China for more than 180 days. Changing from student type to a Tourist L is not necessary.