California requires drivers to stop for pedestrians crossing the road at intersections, whether or not there is a marked crosswalk. California Vehicle Code Section 21950
In this diagram, each of the crosswalks is marked (and in one case, not marked) differently. The law would be the same for all four.
Crosswalks at Schools
Yellow crosswalks are used only near schools, but the law for yellow crosswalks is no different than for others.
(DPT surveys the number of children using an intersection without adult supervision. If the intersection is used by enough chldren, especially if they are walking to public transportation, DPT stripes those crosswalks yellow.)
Crosswalks at Hospitals
Hospitals get no special crosswalk treatment. Hospital signs (even blinking signs) have little effect on driver behavior according to DPT.