Adding a school calendar
It would be great if the program offered a calendar that you can customize for your individual school (start & end dates, vacations) and will allow you to change schedules for special programs or create a coverage schedule.
Maurizio Del Bianco commented
It will be awesome to add a calendar to the timetable, this is how i consider to be the best option.
When you define Days and Periods in the owl you should put a validity start date and end date.
The program could now generate a calendar for those dates which can be used to pin single events, define bank holidays where the school is closed or to see and publish the generated timetable in a calendar view.
This should not be a gigantic effort in terms of development but a massive improvement to the product.