What a nifty idea! if you want creative envelopes, go to Maps, map the route from your letter to the other person's mailbox. Print them up, fold them into 8 by 11 envelopes (or smaller if you are sending cards). This would be cool for pen pals
Use card stock and misc buttons to make your own Christmas cards. The card stock can be bought at Walmart, etc. or at most any craft store. The buttons come in bags at most craft, hobby, or fabric stores.
Snowman activities: Artsonia Art Museum : Artwork by Zachary This is called "Wind-blown snowman." Students could make one of their own with a mini sponge square. On the back, have students write a windy winter story.