Gmail in the classroom as a sub

As a substitute teacher is is hard to establish a new system.  One time I was able to see student progress as they turned in assignments.  It really helped with classroom management as I could see who still needed to turn in work.  If there were a way for teachers to set up "Tasks" in GMail and have the sub see who had completed their work, it would be helpful. (Of course, the sub would need to have access to the GMail.)