Oy, how would I get my dosh!!!!
You could have them mail your dosh checks in advance, for the whole series, or for individual lessons, just don't spend it before you teach them!
Another thought would be if setting it all up yourself might too complex, you could see if you could teach at one of the existing online schools. They'd already have all that stuff worked out.
I took a few online music classes from these guys:
http://www.berkleemusic.com/(where you can get a feel for how they do it without taking a course)
