Why make it hard for yourself and your students to talk with you over the Internet? Why ask students to use a social network to talk with you? What if they don't want to use a social network? What about their privacy?
Don't you want your help available at times you choose rather than each time you turn an instant messenger on?
Cavy comes to the rescue with one-on-one chat (instant messenger) that lets people know when other people will be available.
Like mind maps that have a topic for everything, Cavy has a wiki editor, wiki searcher (search) private instant messenger (chat), issue tracker (issues) & notification system (change alerts). This provides students with the information they need and the help they can request, but also helps you easily create content by assisting you with metacognitive thinking.
Best of all, you set your availability in your availability planner, and so can the students. One place for everything, and unlike many social networks, your conversations aren't used for advertising purposes.
Cavy offers a great solution. Will you care enough to try it out?