Can I continue working (for free) in my University's lab after graduation?

[CICdestroysmylife]

Hi,
As a European, I can stay in Canada as a tourist/visitor for 6 months without needing a visa. I am currently an international student on a study permit, getting a Bachelor’s degree at a Canadian University. I will graduate next year and planned to apply for the post-grad work permit, but I just read that it is only possible to apply for a post-grad work permit once in your lifetime and I already want to apply for it after grad school (I'm undergrad now). However, I won’t go to grad school right away, simply because I need more research experience, another course, and the GRE, all after graduation.
So if I can stay without a visa in Canada for 6 months, does that also mean I can use these 6 months to take one more course and continue being a research assistant (I do this for free, no salary, so technically not a job) in my University’s lab?

Thank you

 

[Buletruck]

If you don’t have a work permit, you can’t work.

 

[CICdestroysmylife]

Yes, I know I can't work without a work permit. But in this case, it's not paid work, so does it even count as working or as something I'll choose to do as a 6 months visitor in Canada, like a leisure activity? All I'm doing is researching something in the lab with five other students and a professor and I'm just wondering where the legal line between what I do and actual work is.