Currently taking graduate course as an Undergraduate
In order to get a good chance to go into graduate schools for Math in Canada and USA, do I need to get a A or A+ in graduate courses as an undergraduate?


I don't think anyone cares too much about the distinction between A and A+, since the standards for what merits an A+ vary so much between universities or even individual professors.


  Or, is A– alright?


This is a little more meaningful, but it's not likely to be the deciding factor.  If you have a great application otherwise, nobody will care about an A- or two.  If your application is not so compelling, getting straight A's won't help much.  This could make a difference, but it's really a low-order effect.