General Suggestions for the Effective Use of Instructional Technology
Require that students use one e-mail address and one username (preferably with their name in it) so they can be identified on the Web.
Make sure you get their address right away, and not just on paper, which often goes awry; ask them to e-mail you.
Explaining online tasks is easier when the students can look at the screen, so either get a smart classroom or bring a TV or projector to class at least once or twice.
It's better to require that students post regularly rather than just a certain number of times by the end of the semester—because they may only post at the end.
Perhaps suggest to students that they write their posts in a word processor and then copy them to the blog, which may save some grief.
Students should be encouraged to edit their work online just as much as they do offline. However, in order to foster dialogue, try to engage with student posts on the level of content rather than mechanics.
Student wikis are more likely to be successful if it is a topic the students feel they are experts on—if it is a matter of simple observation or interpretation, for example.
The Google habit is sometimes deleterious to student research skills, but you can combat this by using Google in class. Demonstrate to students how they need to be discriminating about sources and information that they find online.