John,
Typically what I did was set 4 different timeslots before the course began and put them in the syllabus. I chose very different times/days such as Monday at 2:00 p.m., Thursday at 8:00 p.m., Tuesday at noon and Saturday at 9:00 a.m.
I email all of my students the syllabus at least a week in advance of the course beginning and tell them the four dates/times. I also tell them they have to arrange their schedule so that they can attend at least 2 of the 4. I record them all so if they are not in attendance, they… >>>