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  • Enter the unavailability of the lessons

Lessons inherit the unavailability and preferences of their resources: teacher(s), class(es), room(s), and equipment.  You can add unavailability and preferences specific to lessons. This allows you, for example, to assign specific time slots to lessons in certain subjects for certain classes.

1. Distinguish between unavailability, optional unavailability, and preferences

Unavailability (red)

Unavailability (red) should be reserved for essential cases, when the lesson is not supposed to be held during a time slot. During automatic placement, EDT does not place any lessons in its unavailable time slots. 

For example, if 9th-grade math classes are never held in the afternoon, you mark all afternoons as unavailable.


Optional unavailability (orange)

Optional unavailability slots (orange) are used to indicate the time slots during which it would be preferable for a lesson to be held. During automatic placement, optional unavailability is treated by EDT as unavailability until you decide to ignore it in order to resolve lesson in failure. 

For example, if it is truly preferable that math lessons not be scheduled in the afternoons, you can set optional unavailability for all afternoons.

 

Note
When you decide to ignore optional unavailability to resolve lessons in failure, these are the optional unavailability for all lessons, which are temporarily ignored. Therefore, do not enter mandatory requirements as optional unavailability.

preferences (green)

The preferences (green) allow the specify the time slots during which it would be preferable for a lesson to be held. During automatic placement, EDT tries to take these into account, but they are by no means guaranteed, unlike unavailability or time constraints.

For example, if it's better (though not important) for math classes to be held in the morning, you should list that preference every morning.

2. Enter a lesson's unavailability or preference

  1. Go to the display Timetable > Staff > Unavailability, preferencees and constraints and select the lesson.
  2. On the right-hand panel, above the time grid, make sure the correct paintbrush (red, orange, or green) is selected.
  3. If unavailability has already been entered for the resources for the lesson, they appear on the schedule with a gray hatched pattern.
  4. Click and drag the paintbrush over the time grid to paint the time slots affected by unavailability or a preference.

3. Delete an unavailability or a preference for a lesson

To delete an unavailability or a preference, select the paintbrush of the same color and click and drag over the painted area.



4. Enter an unavailability or a preference for a multi-selection of lessons

If several lessons have the same unavailability, you can enter them in a single operation. To do this, select all the concerned lessons, then click and drag the red paintbrush on the grid.
For example, you want all 9th-grade math lessons to never be held in the morning.



Advice
There are several ways to quickly select all lessons in a subject for a specific level. You can use the shortcut Ctrl + E (Extract > Specify an extraction) from the list of lessons or extract lessons from the list of subjects (or classes) using the shortcut Ctrl + U (Extract > Extract the lessons of the selection) then sort the list by class (or subject).
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