Wikis 4 Educators
Here's the link straight to the wikispaces for educators site. I recommend we use this link to make sites for class use because it has NO ADVERTISING (other wiki types come with it and the ads can be inappropriate :).

Video Explanations
Try this link for helpful (short) video explanations.

How to set up a Wiki site
How to join up and edit pages - (Slideshare by Jacqui Sharpe :)

"How to" explanation - from Suzie Vesper
Editing a Wiki Spaces Wiki