It's entirely up to you!

If it's been more than two weeks, I have no problems canceling classes for unresponsive students unless we were right in the middle of working on something and I had a heads up that something might be going on in their life and they just wouldn't be around for awhile.

(I say this as I see Kindred staring me down from behind, tapping his foot and saying "Uh huh and where is the review we were working on, Missy? Huh? --- I started his class a year ago and I still haven't graduated! Ha)

Depends, If I have not ever heard from them aside from the request, I cancel before a month. If I have talked to them a few times, I will wait it out and see. However, most of the time, I have been blown off. I send messages saying, I will cancel by a certain date unless I hear from you and if I don't hear from them, I cancel. I have 2 unresponsive students right now. I have had to cancel class 6 times since October.

However long you decide works for you, just make sure you give them a window. For example, "If I don't hear back from you in two weeks, I'll cancel the class."

Real Life happens, we just have to deal with it.

It depends on everyone, I haven't canceled anyone because I know sometimes real life gets in the way and sometimes things are out of our control. I suppose if I didn't hear from them for several months and tried to contact them several times, then I'd cancel the class.