"A student who didn’t show up for class on Monday morning just Facebooked me to ask where the class was. I am not responding to a Facebook message! Cripes!"
...um. This just makes me splutter in incomprehension.
Why on earth would a professor bother to set up a Facebook account and then refuse to use it to communicate with students? Yes, it's possible that she set it up to network with friends and colleagues, but I'm willing to bet at least a dollar that that isn't the case here. If it were, she wouldn't consider text transmitted via Facebook's server to be somehow inferior to text transmitted via the campus e-mail server.