This is a great activity to use with your students on Pi Day! The goal is for each student to write a "Pi Day Card" to someone they look up to whether it's a teacher, parent, etc. Within their message to that person, the goal is for them to use some "Pi day words."
The teacher has the option of how much in-class time they want to give their students to do this activity. The activity can easily be done within 15 - 20 minutes, or you can have your students be come creative and give them more time.
If time allows, it's always fun to give students time to go deliver their card to that person, if possible.