My classroom mailboxes are made from gallon cardboard milk or juice cartons. I ask the students to bring them in the first week of school. I cut off the tops, staple them together in rows, use craft paper to cover the sides and use labels to put the kids' names in alphabetical order. I include a box for my assistant and myself. I can replace the kids' names and use the mailboxes over again the next year. I use the mailboxes to send positive notes or thank you's to the children. Sometimes I put in special rewards or surprises for the class. This is also an easy way for the students to distribute their valentine cards. I have a writing center where the children can use their invented spelling to send notes to each other. They love getting and receiving mail!