Huh, interesting -- why doesn't California have school buses? I could imagine it might be hard/unsafe in dense urban areas like SF, but otherwise, why?
I don't know the full reasons, but after some reading: The really short answer is that it's not required by law, but it costs money.
Note that in California the overwhelming majority of schools have a budget that is essentially dictated by the state (the state makes up any shortfall in local taxes up to a certain amount adjusted per-student-day, and most schools are in districts that have such a shortfall). This means that there are only two ways to provide buses: charge students who ride buses (done in some districts) or take money out of the classrooms (not popular with parents nor teachers' unions).
Where I grew up there was a time when they needed to upgrade the bus fleet, so they passed a bond specifically for that purpose. If I understand the law correctly, this wouldn't be feasible in California outside of basic-aid districts (basic-aid districts are those that do not have a shortfall in their general funds, so they only get the "basic aid" for that is earmarked for special-ed &c.).
> Where I grew up there was a time when they needed to upgrade the bus fleet, so they passed a bond specifically for that purpose. If I understand the law correctly, this wouldn't be feasible in California outside of basic-aid districts
You misunderstand the law, all school districts in California can submit bonds to the voters of the district, and this is a routine method of addressing capital needs.