Protagonize is a wonderful free site where people can collaboratively create versions of “choose your own adventure” stories. However, until today, it was problematic for teachers because you couldn’t regulate contributors.
Now, however, you can private groups.
You can read the announcement here, and get questions and answers here.
Protagonize is on two “The Best…” lists:
The Best Sites For Collaborative Storytelling
The Best Places To Read & Write “Choose Your Own Adventure” Stories
Hey Larry, thanks much for the mention!
Just wanted to note that while the site does support “addventure” stories (aka. Choose-your-own-adventure), the vast majority of the works submitted on the site are standard, linear writing. We also support the submission of both collaborative and solo/individual writing, poetry, writing exercises, and much more.
-nick / protagonize