Importance of modifying existing timetables

[Vangelis Karafillidis]

In my country (Greece), schools need to modify their timetables quite many times during the school year. The reason is that not all teachers are hired at the beginning of the school year. Actually, teachers are hired "incrementally". So, up until February (or even March/April) schools need to change their timetables, each time new teachers are hired. The problem is that there is a practical necessity of modifying the previous (existing) timetable in such a way that each day "preserves" its activity content as much as possible.
My suggestion is to add a button at the generated timetable view, so the user could select the activities he/she wants and add a constraint, so that the selected activities would be placed in the new timetable in selected time slots. In this way, the timetable will change of course, but it would not affect the test planning of the school, etc.
What do other users think? Would this feature be useful for their schools? Greece might be an exception... Who knows?

Vangelis

[Darren McDonald]

I don't know that I would use this feature, but (if I understand your aim here) this could be accomplished if there were an option to add a new activity tag to selected items in the timetable view. (If you could add a new tag to selected activities, you could then use "Lock all activities with a specified activity tag" to keep them in place.)

[Vangelis Karafillidis]

This is not exactly what I mean. Locking activities in specific time slots is a very strong constraint. Preserving the activity content of each day (or nearly preserving) is not such a strong constraint. What I mean is one can preserve the activity content of the day, without necessarily locking specific activities in specific time slots. For example ensuring that the activities which are placed on Monday, will again be placed on Monday, but in a different order, is enough for schools to don't worry about their planning (for example tests). So, any way of defining which activities should be constrained in specific days would be enough for this. I was thinking of adding a constraint of "a set of activities has a set of preferred time slots" would be enough. For example, one could select the Monday activities and constrain them in this way. Or to do this for any day, or even each day. Also, it would be very useful if one could add a comment, in order to discriminate between the initial constraints and the new constraints which are added for preserving the activity content of each day.