These monthly calendars are left date-less so they can be used year after year! The key-code allows you to quickly notate behavioral issues you may be having for that child, and to ensure open, parental communication with families at home! This is a great way to keep your student's families up-to-date on behavior, class events, holidays, due dates, etc. Just write it in one master, and run off copies for the whole class for that entire month. Keep them handy in your students' take-home folder