If students are missing an assignment, I use this small sheet and staple it directly into their assignment notebooks. It's a fast and easy way to let parents know an assignment is late and needs to be returned as soon as possible. It can easily be taken off of a student's assignment notebook after signed by a parent and stored in a file (should you need documentation of consistently missed homework).
On this sheet, it is stated that a letter grade will be deducted if an assignment is late. I'll also post a sheet just like this but leave off the deduction of a letter grade (if you'd prefer).