Sending a camera across the country for postal workers to use for pictures.
Throw paint-filled eggs at canvas. We're totally doing this one day! Outside project!
Sand from places we've been
How fun! Made from Potatoes!
Envelope art from Japan incorporating the postage. Clever!
Mail art envelopes Fun
Who doesn't love mail? Great tutorial for making a DIY cardboard mailbox for kids
Thema post / communicatie
Great idea! (Magnetic puzzles-use on a cookie sheet during car trips)
Craft - brownies
lunch notes or could be a note from a teacher to student