Wikis

...As a teaching tool
Bronte and I actually set up a Wetpaint account last year with the intention of using it to create a web quest. We ended up using PowerPoint instead and so I never became familiar with the Wetpaint site.
So wanting to learn more about Wetpaint I created a Wiki with them. Establishing the site as home of TEACHER (The Educational And Creative Http of Exciting Resources...and yes that took me ages to think of!) I suddenly realised the enormous potential for teacher collaboration by using this site.
If a collection of teachers were to subscribe to this group, effectively we would become a community of practice. Etienne Wenger (2006) defines communities of practice as "groups of people who share a concern or passion for something they do and learn how to do it better as they interact regularly".
As for a Wiki's role in the classroom? The question really should be does a Wiki need to be part of the classroom routine? Initially, students will need some scaffolding in how the Website works, although the informative help button is always close at hand. Once students now how to add to the site there should be few problems.
Wiki's would be perfect for problem solving actvities, reasearch and planning. The Wiki could be created as a whole class where smaller groups can work on different aspects of the one topic or many topics worked on by many groups.
...for students
Students have much to gain from working with this sort of site. The YouTube Clip found on Moodle is a great example of student interaction, however as mentioned above, this site is also the perfect setting for collaborative learning.
Before we go on, it is important that we now recognise that learning is not something that takes place solely in the classroom. Wiki sites enable students to be physically separate but mentally together. This has both advantages and disadvantages.
Advantages

• Students can become part of a collaborative learning environment whereby they are engaged in "active cognitive processes such as creating, problem solving...and decision making (Kearsley & Schneidermann)"
• Students are more likely to be motivated to learn within a group setting
• Collaborative learning forces students to voice their problems however there are many brains available to help find a solution
  
• Students will work with others who may have backgrounds that are quite diverse from their own, allowing social skills and different view points to develop.
• Students who cannot regularly attend school can still be a part of the learning environment and be actively engaged in learning tasks
  

(Kearsley & Schneidermann)
Disadvantages

• Not all students will have access to internet or computers at home

In this case students will need access to computers at the school either before or after school (however, family situations/commitments/outside factors may prevent this) or during school hours.
A Wiki, when facilitated properly can be a valuable learning tool for both teachers and students.