January deadline:

• Ann Arlys Bowler Poetry Contest
  Sponsored by Weekly Reader
• Hurston/Wright Award for College Writers  for students of African descent
  Sponsored by the Hurston/Wright Foundation
• NCTE: Promising Young Writers  for 8th grade students (US, American Schools Abroad, & Canada) who have been nominated by their schools.
• NCTE: Achievement Awards in Writing  for high school juniors
• Scholastic Art and Writing Entry information available on web site
• Trollope Society Short Story Prize  open to students 21 years old and younger
  Sponsored by the Trollope Society
• The Writing Conference, Inc.'s Writing Contest

February deadline:

• Highlights Fiction Contest
• Kids Philosophy Slam 
• Nelson Algren Awards  sponsored by The Chicago Tribune
• Playboy College Fiction Contest
• Paul A. Witty Outstanding Literature Award  for elementary and high school students (link is an MS Word file)

March deadline:

• The Claremont Review Annual Writing Contest  entry fee that includes a one year subscription to magazine
• Commonwealth Essay Competition - Write Around the World
• Kids Are Authors Contest  (Scholastic) K-8
• The PUSH Novel Contest
• The Stony Brook Short Fiction Prize  limited to U.S. and Canadian undergraduates

May deadline:

• David Melton Memorial Written & Illustrated by… Contest for Students
• Kay Snow Writing Awards  (Student Writer)
• Teen Ink Annual Fiction Contest

June deadline:

• Delacorte Dell Yearling Contest for a First Middle-Grade Novel
• The Fire Escape Writing Contests for Teens Between Cultures

October deadline:

• Final deadline for ARTS Recognition and Talent Search sponsored by National Foundation for Advancement in the Arts
• New Voices Award  sponsored by Lee & Low
• Zoetrope: All-Story Short Fiction Contest

November deadline:

• Atlantic Monthly Student Writing Contest

December deadline:

• Delacorte Press Contest for a First Young Adult Novel
• seventeen's fiction contest 
• Young Communicators Fellowships  awarded for strategic short-term opportunities to pursue careers that involve the communication of ideas.

Other sites to check for writing contests

• Amazing Kids! eZine Art and Writing Contests  age categories from 6 to 17
• Assignment for Kids  monthly contest for kids 13 and younger sponsored by  WritersDigest.com
• Annual Young Writers and Illustrators Contest  for students kindergarten through 3rd grade is sponsored by PBS stations across the U.S.
  Find your local contest at this site. Submission dates vary by station.
• Cricket League Contest  Art and short story contests sponsored by Cricket Magazine.
• Random House previously published Twentysomething Essays by Twentysomething Writers: The Best New Voices of 2006
• Weekly Reader, publisher of READ and Writing magazines, frequently has writing contests.
• Letters About Literature  sponsored by The Center for the Book in the Library of Congress, in partnership with Target Stores
• Oprah previously sponsored  Oprah's National High School Essay Contest