Hi,
I had the same situation. My husband is holding GC from US and will be citizen in few months, though I applied under SPP and got the visa in 2 days. I suggest you show that your husband is working and he has enough annual income to support you. Include his Job appointment letter, last 6 months Pay slip, last 2 years of tax returns (if there are any or else its fine), marriage certificate, his passport and of course his Green Card copy. US and CANADA is having friendly Immigration relationship hence I do not see any hurdle for you.
1) Your Green Card files proves that you do not have any immigration intention.
2) If your husband has a good job or business, then it proves that you will not be working illegally and not interested in any short term financial gain by working. Also, it proves that you are a legitimate student who will pay the fees and leave once study is finished.
Zia