Creative Writing for Teens at About.com
A great inspirational site for young writers.
On-line writers group that allows postings and critiqueing.
Merlyn's Pen lets you read and submit literary works.
Teen Ink is a well-known magazine for teen writers, and their Web site is another place for teens to publish.
Writing World offers useful articles for writers to peruse, many applicable to teen writers. Also has listings of contests.
Not sure how to cite your sources? Go here and find out.
This is a very easy, thorough way to create a works cited page or annotated bibliography.
Humanities reference site, Voice of the Shuttle
Internet Public Library
Find it all in one place.