Keeping track of student work when they are absent can be difficult. In my classroom a student is assigned to be the "substitute" every week. That student is in charge of keeping track of work when a student is absent. This document and worksheets are placed in a folder for each student absent. Even if this is not your method for dealing with absent students, this document can be a great tool.
*I like to make a photocopy of this before it is sent home.