Students discover a magic mailbox on this worksheet that can send letters back in time. They have to write a letter to someone in the past whom they have had trouble with and explain how they feel about what happened now. It's a great activity for self-reflection while giving students the ability to practice general writing skills, like spelling, punctuation, and compound sentences. There's room at the bottom to write about whether they would ever send a letter like this in real life, further encouraging self-reflection.