Week 4 Thing 7 and 8 wiki

I am not quite sure if I would use a wiki in a second grade classroom.  I can see many applications for older students maybe 6th grade and up.  I did however find a few ideas that could be useful like making a class scrapbook or collaborating with another classroom on writing a futuristic fairytale.  I would really like to see someone actually using one.  I'm a visual learner---