I use this activity at the end of the year. Students complete surveys, as well as other activities (see my other Time Capsule products, then seal them in their own time capsule (manila envelope) that they cannot open until right before their high school graduation. In this activity, students write a letter to their friends, and I place them in the appropriate time capsules. I don't let them read the letters they write to each other. It increases the surprise when they open their time capsules in the future. It is exciting for them to see what they wrote as 8th or 9th graders when they are getting ready to leave high school as "adults".