How to set teacher's timeoff
In Teachers dialog you can specify when each teacher can teach. It is possible to set this in menu Specification - Teachers - Time off.
By clicking on a particular day (in row) or a period (column) you can turn whole row or column into desired option. By one click you can set that this teacher cannot teach e.g. on Mondays or can not be teaching on 1st period.
If you have teachers who teach only two days per week and it doesn't matter which ones - please see also:
We have teacher who teaches only 2 days per week and it doesn't matter which