NaNoWriMo is an international initiative providing a forum for teen writers to be able to share their work, work collectively towards writing goals, and ultimately, to write a novel during the month of November.
If this sounds like something you are interested in check out the NaNoWriMo website.
There is more information here about how the programme works.
Wellington City Libraries have their own classroom group set up and have invited anyone who is keen to join them. Check out their blog post here.