Sub·mit·tal PLEASE leave a clue for when it's "due"

Teachers will often leave lesson plans without clearly indicating when assignment(s) are due (and preferably the same hour). Without a clue for when it's due, most (not some or many) will predictably blow-off or defer work.  It has the effect of announcing "recess"!  Having served in hundreds of classes with thousands of students over the span of 10 years, I have never seen an exception to this mishap. Sure there are always a handful of conscientious students who will make-haste in accomplishing the assignment in class -even without a clear due time made known, but they are the exception.  Most, will interpret absent or delayed due time as an invitation to play and is often the case, they want to "play the sub" before a captive audience. A lack of forethought or advanced, strategic planning will almost inevitably present ready-made opportunities for misbehavior. With the ever-decreasing attention span of adolescents today, it is imperative for teachers to clearly review with all students their expectations for a guest teacher's anticipated arrival (think of it as your own personal vacation insurance/assurance -foster a trust with a good sub as part of your emotional refueling or margin-setting goals) BEFORE they evacuate the building.  And among expectations of utmost importance is a teacher's expected due times for submitting work.  Without that clear directive from the teacher, I sometimes am left with having to summarily impose "due" or expected submission of work (competed or not)  for the duration of the sub-assignment. I realize that such an assumption may be risky, but  without a clue for when work is due, the hazards of "advancing the educational process" become manifold -fought with behavioral landmines throughout an entire day of classes. None of us (teachers, administrator, subs and especially good students) want to distress and already stress-charged dynamic when a sub is in the classroom. I fully understand that skillfully dealing with misbehavior should be an anticipated part of the job (and honestly it can be done positively when we know that administrators have our backs).  However, if we can prevent even some disruptions by practicing the discipline of making clear due times within our plans, then we might well avoid some of the behavioral melt-downs that far too many of us have encountered.  The old adage is true, "an ounce of prevention is worth a pound of cure".