Have your students complete a daily Vocab challenge at:
Unbelievable free writing resource for teachers:
http://www.writingfix.com/picture_book_prompts.htm#top
10 Amazing writing resources for kids:
http://imaginationsoup.net/2011/08/10-amazing-writing-activities-and-resources-for-kids/
Kids writing resources:
http://www.netrover.com/~kingskid/writing/Kids_Writing.html
Fun Writing Games for Kids:
http://www.funenglishgames.com/writinggames.html
A lot of the resources found her could be adapted into Google Docs :
http://teacher.scholastic.com/professional/teachwriting/
This web says 4-6th grade but could be easily adapted for secondary ed too:
http://www.aasd.k12.wi.us/staff/boldtkatherine/WritingResources.htm
150 Writing Resources:
http://oedb.org/ilibrarian/150-writing-resources/
Free Writing Resources:
http://www.time4writing.com/free-writing-resources/
Writing Resources:
http://garbl.home.comcast.net/~garbl/writing/#.U8H7bPldWSo
50 resources that will improve writing skills:
http://www.smashingmagazine.com/2009/06/28/50-free-resources-that-will-improve-your-writing-skills/
Purdue University online writing lab:
https://owl.english.purdue.edu/owl/section/1/
Newspapers:
http://tewt.org/index.php/research/newspapers
Prewriting and Inspiration:
http://tewt.org/index.php/lessons-activities/pre-writing
Digital Citation Generators:
http://tewt.org/index.php/research/citation-generators
Video writing prompts:
http://www.teachhub.com/video-writing-prompts
Writing and Research:
http://edtechteacher.org/tools/research/
A Teacher's Bag of Tricks--Writing:
https://sites.google.com/site/ateachersbagoftricks/writing
Writing Fix: Quality Resources for Teaching Language Arts:
Video Resources: