> It creates unusual demand patterns on schools and daycare which you need to decide whether to run on a four or five day pattern.
Schools can run a 5-day pattern even if some of their employees are on a 4-day pattern (as long as they are not the same four-day pattern). In fact, it's not unknown for various workplaces to run a 5-day every week pattern with employees on a mix of 9-8-80 two-week and 4-10-40 1-week cycles with different cycle days off.
Faculty (especially in pre-K through primary grades; scheduling can be more creative without disruption at the secondary level) probably need to be on every open day, generally, but other than that,..
It's difficult and disruptive for students to be on a 5-day pattern of education with a homeroom teacher on a 4-day pattern. This basically necessitates scheduling entirely non-core subjects on the fifth day, potentially even resulting in multiple sessions of gym in a single day. It's also not clear to me you can viably do this without increasing costs unless the school is free to choose which of the four days the teacher's work instead of the teacher doing so. For example, if the standard 4-day work week is Monday-Thursday then there is ridiculous demand for non-core subject teachers on Friday and those non-core subject teachers may even be working Monday-Thursday themselves resulting in reduced supply.
> It's difficult and disruptive for students to be on a 5-day pattern of education with a homeroom teacher on a 4-day pattern.
Is it? In most secondary environments I’ve seen “homeroom”, if it exists at all (which tends to only be early secondary, like middle school, and not consistently even there), is simply a regular class to which added time for administrivia like daily announcements is added.
Schools can run a 5-day pattern even if some of their employees are on a 4-day pattern (as long as they are not the same four-day pattern). In fact, it's not unknown for various workplaces to run a 5-day every week pattern with employees on a mix of 9-8-80 two-week and 4-10-40 1-week cycles with different cycle days off.
Faculty (especially in pre-K through primary grades; scheduling can be more creative without disruption at the secondary level) probably need to be on every open day, generally, but other than that,..