I encourage my kids to write reminder notes like school supplies or groceries I should remember and Notes for Dad to let him know we went to the park.
Do you kids like to draw? Words can be added to pictures. You might try leaving some inspirational books around. I have best results with just one or 2 appealing books at a time, rather than a stack. If you just pick up a book to read they might just come over to share it. If you make a book they might like to get involved.
More Library or web for ideas: write songs and plays, video tape a story board acted out, Poetry magnets, comics strips, book making, writing prompts, journals (nature, trip or summer), card making, poetry, letter writing, post cards. You might get a rhyming dictionary.
http://www.shelsilverstein.com/pdf/poetry.pdf (make a poetry puzzle, like word magnets)
http://www.loreenleedy.com/ The Furry News: How to make a Newspaper
Look at My Book: How Kids Can Make Terrific Books
Messages in the Mailbox writing letters
Look at My Book: How Kids Can Write and Illustrate Terrific Books
http://www.eduplace.com/tales/similar to Mad libs
http://www.makebeliefscomix.com/ make comics
http://teacher.scholastic.com/writewit/poetry/poetry_engine.htm#http://www.shelsilverstein.com/html/Teachers.htmlLibrary mouse / Daniel Kirk (My kids made their own little library at one time. This book might encourage book writing)
You Can Write a Story! : A Story-Writing Recipe for Kids by Bullard, Lisa; Melmon, Deborah H.
Cartooning : the only cartooning book you'll ever need to be the artist you've always wanted to be / Art Roche.
http://www.klutz.com/kid/express-yo...pnav_kid_express-yourself///nav/txtl////http://www.americangirlpublishing.com/advice/beyourbest/WritingSmarts.aspxCreative Writing By Children
The Print Magazine for Kids Who Love to Read. Established in 1973, Stone Soup is the leading publisher of children�s writing and art in the English-speaking world.
www.stonesoup.comThis should keep you busy for the whole summer.
Keep us posted on what works. This is a great thread. (I enjoyed the diversion in finding all of this)