I always thought the reason school days go from 7-3 or 8-4 (or whatever) is usually more about bus scheduling and logistics. And high schools historically start earliest (despite it being worse for teens) so older siblings will be home and can watch younger siblings after school.
Maybe that’s just what I was told growing up but if every school did 9-5, they would need more bus drivers.
If you’re just looking to learn something new, why not try an immutable OS like Fedora Silverblue? It’s an easier install than Arch, obviously, but there’s lots of differences from a standard distro. There’s security upsides but also consequences to work around.