[AidenVennis]

At least in The Netherlands, about 15 years ago when I was in high school, timetables where set for a whole semester, but absent teachers where quite normal meaning some lessons where canceled. Replacements where not always available and where usually only deployed when it was known a teacher was absent for extended time.

As a teen this was great because sometimes you could stay in bed longer, be out earlier and not having to carry the extra books (not sure if that still is a problem now).

edit: I just remember we even had call trees to call your classmates in the morning if classes got canceled. This was before the internet, making it not 15 years ago but at least 20, probably more. I'm getting old...

[globular-toast]

I went to school 20+ years ago in a school of 3000+ kids in the UK. There simply never were room changes for us. I don't get why you'd make the kids change rooms. Just set the timetable for the year, now the kids are going to be in those rooms at those times. Simple. Any changes, just make the teachers deal with it. In a system where the children outnumber the teachers ~30:1 and have smaller brains and smaller bodies this seems to make more sense to me.

As for cancelled lessons, I wish! That never happened. We had a substitute teacher every time. But the substitute came to the room we were already scheduled to be in.

The only reasons I can think for making the kids change is if there's a problem with the room itself or if the teachers are not interchangeable between rooms. But I would have thought teachers would find room changes easier now than back then, if anything (given the use of ubiquitous technology like projectors etc.).