@Jes2G @Psychotps While I completely agree that it would be nice for university students to have holidays off, I can also see that such an implementation would lead to issues:
For example, some players have a whole bunch of custom holidays clumped together, such as summer vacation or the winterfest to end-of-year period. At what point does a term become too long, especially when there are no holidays? There's also the problem of what happens when one adds a new holiday during a term, or modifies an existing holiday from work-as-normal to off-work. Does the class schedule get re-calculated each time? What if a holiday is manually deleted? Or what happens when a player decides to change the entire length of seasons?
So to be honest, I rather get comfortable with the idea that sim students just have to go to university during holidays than having to deal with the dozen or so new bugs this would certainly introduce.