In ARCADE there is no distinction between the deadline and the scheduled session for an exercise. A module is taken by a number of students divided into groups. The work for a module is divided into a number of sessions. Each group is allocated a date (and time) for each of the sessions. Sessions may be given a deadline. This means that the deadline for the work associated with that session (and previous sessions since the last deadline) is the end of that session, for that particular group of students. However, an individual student has a right to obtain an extension of that deadline to the start of the next session, without any penalty. If he or she does not complete the work by the deadline, and either fails to obtain the extension, or fails to complete by the start of the next session, then that piece of work is flagged as being late.
Late work carries a heavy penalty, but one which inherently cannot cause a student to fail a module. Late work is marked in the normal way, but when the overall mark for the module is being calculated, the late and non-late portions are computed separately. If the non-late mark is already bigger than the pass level, then the late work is completely ignored! Otherwise, if the sum of the two is greater than the pass mark, then the pass mark is awarded. If neither of the above are true, then the overall mark is the sum of the late and non-late marks.
The author's experience of using this regime for two successive sets of first year students and one set of second year, is that it works very well in achieving the stated aims of encouraging the best work pattern from the students. They quickly realize that it is in their interests to do much of the work for an exercise before its scheduled session, so that they can make use of the laboratory staff should they need to.
There is, however, an axiom here that the only (normal case) reason for students to have a late flag is that they are not working hard enough. (There are mechanisms for dealing with exceptions - see the next section). This is how it should be, but sometimes those responsible for setting exercises are slow to accept that they are expecting too much! The author believes this to be a good feature of the regime: it (perhaps eventually) enforces the correct pitching of the difficulty of the work, rather than allowing a poor match to be hidden in the students' bad time-management.