When instructors must take time off, for whatever reasons, and if they are unable to leave or make lesson plans readily available to substitutes, school administrators should take it upon themselves to produce the lesson plans. While subs may teach and produce sporadic assignments for students, unless the students are completing required and/or assignments that are due at a given time those assignments are essentially obsolete, even if they are mastered. Students should be taught on schedule and graded only on course material introduced within relevant grading periods.