The Daily Behavior Sheet (DBS) is a great way for teachers to quickly and easily communicate with parents/guardians every day. There's a check off list for behavior, effort, and homework/classwork. There are also sections to write in any missing assignments and other notes about the student. Finally, there is a sport for a parent/guardian signature.
I have been using this form for years and it has been a great communication tool, as well as documentation that you have made parents/guardians aware of any issues.