After having assigned the activities to the rooms I was eager to see some results and tried a first simulation...
The outcome was quite disturbing. I got a message saying that the total of activities exceeded the available hours so 38 for 34 hours available...
I checked the activities and found 25 hours for the mentioned group.
this is how I checked the total of hours...
I don't know if the reason is to be looked up here... I created an activity for the whole grade 10 as the English class is divided into three groups Low Medium and High.
Three teachers teaching at the same time...
Or (see the other picture) because Humanities students have English Literature (2 groups) and optional Chinese or French, so I put these activities at the Grade 10 Humanities level and not at the the subgroups level.
I couldn't add the picture on the previous post...
The problem is with optional Chinese or French. You should add an activity with subject "Opt Fr-Ch" and add only once (so 4 hours in total in 3 activities with this subject). You added 4+4 hours, and in this way you add only 4 hours, so that is where the problem came from (34->38).
I think what the error means that from your data and constraints, your needed period is 38 (hours/period) BUT your FREE period is ONLY 7x5=35 (periods/hours).
So, you need to extend that 7 to 8 so that 8x5=40. :)
No the first answer was the right one. I put too many hours due to a wrong information given by one of the teachers.
In the meantime I could simulate a good timetable and I must say this program is great, powerful!
I hope to have some time available to explain step by step how I achieved it.