I'll piggyback on Joan Waites' Snowy Day post and share a holiday season idea that I adapted from poet/teacher Kenneth Koch. Wish Poems. First gather up the kids and have a chat about wishes. What is a wish? Have you ever had a wish come true? Does a wish have to come true for it to be meaningful? What are you wishing for right now? What do you think your grandmother (or your goldfish or that old man who lives on the corner) is wishing for?
After brainstorming for a while about wishes, write two wish poems...one silly and one serious. I really believe in the importance of letting kids express both types of sentiments. The wish poems can be illustrated and/or shared aloud.
Finally create a special box for secret wish poems and explain that anyone can write a secret wish poem and that the author should NOT sign his or her name. Kids can put a secret wish poem in the box anytime. Secrets generate a lot of interest and even your reluctant writers will want to do this. After about a week or two, on a specified day, share the secret wish poems aloud, not revealing the authors. I guarantee that your students will love this activity.
Make sure to check out Koch's wonderful book, Wishes, Lies, and Dreams: Teaching Children to Write Poetry.