Expository Writing Prompts
Expository Writing Prompts, Grades 1-3
Bright Ideas for Writing, Grades 1-2 (Houghton Mifflin)
http://www.eduplace.com/kids/hme/k_5/brightideas/1-2/description1-2.html

Everyday Spelling - Writing Prompt Index
http://www.everydayspelling.com/workout/prompts/promptsndx.html
Expository Writing Prompts, Grades 4-6
Bright Ideas for Writing, Grades 3-5 (Houghton Mifflin)
http://www.eduplace.com/kids/hme/k_5/brightideas/3-5/description3-5.html
Can Teach
Long list of prompts.
http://www.canteach.ca/elementary/prompts.html

Everyday Spelling - Writing Prompt Index
http://www.everydayspelling.com/workout/prompts/promptsndx.html

Jefferson County Schools
http://jc-schools.net/write/grade8.html
Expository Writing Prompts, Grades 7-12
Jefferson County Schools
http://jc-schools.net/write/grade8.html